The cephalic lateral line system and its innervation in <Emphasis Type="Italic">Pardachirus pavoninus</Emphasis> (Soleidae: Pleuronectiformes): comparisons between the ocular and blind sides

The cephalic lateral line system and its innervation were examined and compared between the ocular and blind sides in Pardachirus pavoninus (Soleidae). On the ocular side, the otic and preopercular canals were partly (posteriorly and dorsally, respectively) formed by canalized scales (one and five, respectively), each containing a canal neuromast (i.e., “lateral line scales”) and innervated by the anterior lateral line nerve (otic and mandibular rami, respectively). The canal neuromasts of the five scales were recognized as homologous with superficial neuromasts in other taxa based on innervation. The scales, each with a canal perpendicular to the long axis of the scale, bridged the wide gap between the otic region of the cranium and preopercle. The superficial ophthalmic ramus was bifurcated on both sides, the dorsal ramule emerging from the cranium via a frontal foramen. The buccal ramus on the blind side was intensively ramified in the area made available by migration of the eye to the ocular side. The numbers of canal and superficial neuromasts differed greatly between the sides, being 19 and 173 on the ocular side, and 1 and 465 on the blind side, respectively. Sensory strips of superficial neuromasts on the blind side had clear long and short axes. Numerous dermal papillae occurred on the blind side, forming complex channels, according to directions of the long axes.     

The innervation and adaptive significance of extensively distributed neuromasts in <Emphasis Type="Italic">Glossogobius olivaceus</Emphasis> (Perciformes: Gobiidae)

Components of the lateral line system and their innervation were examined in Glossogobius olivaceus (Gobiidae), with almost all of the trunk scales bearing a row of superficial neuromasts, the latter comprising some 2,900 of the total (ca. 4,800) neuromasts on the body. The relationship between orientation and innervation of the superficial neuromasts on the head showed the buccal and mandibular rami to be clearly separated. On the trunk, the lateral ramus detached a number of branches, typically comprising dorsal, lateral and ventral ramules, to innervate neuromasts. Extensively distributed neuromasts were considered as an adaptation to a nocturnal habit, compensating for reduced vision.     

Lateral line system and its innervation in Tetraodontiformes with outgroup comparisons: Descriptions and phylogenetic implications

The lateral line system and its innervation in ten tetraodontiform families and five outgroup taxa were examined. Although some homology issues remained unresolved, tetraodontiforms were characterized by having two types (at least) of superficial neuromasts (defined by the presence or absence of supporting structures) and accessory lateral lines and neuromasts (except Molidae in which “accessory” elements were absent). The preopercular line in Tetraodontiformes was not homologous with that of typical teleosts, because the line was innervated by the opercular ramule that was newly derived from the mandibular ramus, the condition being identical to that in Lophiidae. Within Tetraodontiformes, the number of neuromasts varied between 70 and 277 in the main lines and between 0 and 52 in accessory elements. Variations were also recognized in the presence or absence of the supraorbital commissure, mandibular line, otic line, postotic line, ventral trunk line, and some lateral line nerve rami, most notably the dorsal branch of the opercular ramule, being absent in Aracanidae, Ostraciidae, Tetraodontidae, Diodontidae, and Molidae. Morphological characteristics derived from the lateral line system and its innervation provided some support for a sister relationship of tetraodontiforms with lophiiforms. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.     

Homologies of cephalic lateral line canals in <Emphasis Type="Italic">Pseudorhombus pentophthalmus</Emphasis> and <Emphasis Type="Italic">Engyprosopon grandisquama </Emphasis>(Pleuronectiformes): innervation and upper eye floor formation

Cephalic lateral line canals in two pleuronectiforms, Pseudorhombus pentophthalmus (Paralichthyidae) and Engyprosopon grandisquama (Bothidae), were studied and their homologies between the ocular and blind sides assessed on the basis of position and innervation patterns. A blind side canal, comprising small ossicles in a line lateral to the upper eye floor, was confirmed as the infraorbital line because the canal was not innervated by a ramus associated with the upper nasal (i.e., the superficial ophthalmic ramus innervating the supraorbital line). Consequently, the ramus innervating the canal was identified as the buccal ramus (associated with the infraorbital line). The blind side frontal forming the posterior half of the upper eye floor was identified as that part bearing the anteriormost otic canal in the ocular side, hypertrophy of the blind side component being evident. The supraorbital line of the blind side was represented by the upper nasal only in E. grandisquama.     

Fos Protein Expression in Sacral Spinal Cord in Relation to Early Phase of Cauda Equina Syndrome in Dogs

1. The aim of the present study is to map the incipient phase of Fos expression in the sacral spinal cord neuronal pools of multiple cauda equina constrictions canine model.2. Fos-positive neurons were found bilaterally in the lateral portion of superficial dorsal horn layers (Laminae I–III) and along the lateral edge of the dorsal horn accompanied by the lateral collateral pathway, fibers of Lissauer's tract, terminating at the sacral parasympathetic nucleus. Similarly, high Fos expression was detected in the ventral portion of the dorsal sacral commissure and in the dorsomedial portion of the anterior horns at S₁–S₃ segment level. Finally, a clearly expressed Fos-positivity was disclosed bilaterally in the neuropil of the nucleus Y in the anterior horn.3. Data from the present study show that continuous stimulation of the central fibers of sacral dorsal root ganglia neurons, i.e., fibers of sacral primary afferents, unlike those using various stimulations of the peripheral fibres offers an unusual pattern of Fos-like immunoreactivity.     

Neural ectoderm,neural crest,and placodes: Contribution of the otic placode to the ectodermal lining of the embryonic opercular cavity in Atlantic cod (Teleostei)

Development of neural ectoderm, neural crest, and otic placode with special reference to a new placodal derivative, the ectodermal lining of the opercular cavity, is described in a teleost fish, the Atlantic cod Gadus morhua, from a stage-by-stage examination of embryonic development. The ectodermal lining of the opercular cavity forms by invagination of the otic placode. The neural plate “infolds” by a wave of cellular rearrangement that transforms the neural plate into a neural rod. This transformation creates a distinct dorsal ectodermal cell layer. When the neural rod is arranged as monostratified columnar cells in the forebrain and midbrain, dorsal ectoderm at the midbrain level thickens lateral to the neural rod to form a cell cluster—the presumptive neural crest and placode. Upon migration of the neural crest from the postoptic midbrain, the dorsolateral area of the dorsal ectoderm thickens and segregates from the neural crest as a placode that is continuous with the presumptive lens placode. As the neural crest migrates from the hindbrain, this placode extends along the hindbrain as a single continuous cluster of cells. At the onset of formation of the lens placode, this continuous placode becomes the placode in the postoptic area of the midbrain and separates into the otic placode at the hindbrain. The otic placode gives rise to the otic neuromast and probably the otic lateral line nerves rostrally and to the ectodermal cell lining of the opercular cavity and otic vesicles caudally. The opercular cavity forms by invagination of the otic placode, creating an internal lumen lined by ectoderm that becomes continuous with evaginated endodermal pharyngeal cells. Free neuromasts are observed along the trailing edge of the external opening of the opercular cavity, which lies horizontally, ventral to the otic vesicles. As embryos develop to hatching, the opening rotates and takes up a vertical position. The adult opercular apparatus, including associated bones and muscles, forms during larval stages. The otic neuromast may be a remnant of neuromasts in the spiracle organ. The spiracle opening lies between the mandibular and hyoid arches, whereas the opercular cavity opens between the hyoid and the first branchial arches. The spiracle opening is, therefore, not homologous with the external opening of the opercular cavity, although the cell lining of the spiracle opening may be of placodal origin. J Morphol 231:231–252, 1997. © 1997 Wiley-Liss, Inc.     

Afferent projections of the trigeminal nerve in the goldfish,Carassius auratus

The horseradish peroxidase (HRP) histochemical technique was used to examine the peripheral distribution and afferent projections of the trigeminal nerve in the goldfish, Carassius auratus. Sensory fibers of the trigeminal nerve distribute over the head via four branches. The ophthalmic branch distributes fibers to the region above the eye and naris. The maxillary and mandibular branches innervate the regions of the upper and lower lip, respectively. A fourth branch of the trigeminal nerve was demonstrated to be present in the hyomandibular trunk. Upon entering the medulla the trigeminal afferent fibers divide into a rostromedially directed bundle and a caudally directed bundle. The rostromedially directed bundle terminates in the sensory trigeminal nucleus (STN) located within the rostral medulla. The majority of fibers turn caudally, forming the descending trigeminal tract. Fibers of the descending trigeminal tract terminate within three medullary nuclei: the nucleus of the descending trigeminal tract (NDTV), the spinal trigeminal nucleus (Spv), and the medial funicular nucleus (MFn). All projections, except for those to the MFn, are ipsilateral. Contralateral projections were observed at the level of the MFn following the labeling of the ophthalmic and maxillomandibular branches. All branches of the trigeminal nerve project to all four of the trigeminal medullary nuclei. Projections to the STN and MFn were found to be topographically organized such that the afferents of the ophthalmic branch project onto the ventral portion of these nuclei, while the afferents of the maxillo- and hyomandibular branches project to the dorsal portion of these nuclei. Cells of the mesencephalic trigeminal nucleus were retrogradely labeled following HRP application to the ophthalmic, maxillary, and mandibular branches of the trigeminal nerve. In addition to demonstrating the ascending mesencephalic trigeminal root fibers, HRP application to the above-mentioned branches also revealed descending mesencephalic trigeminal fibers. The descending mesencephalic trigeminal fibers course caudally medial to the branchiomeric motor column and terminate in the ventromedial portion of the MFn.     

北草蜥中脑视叶组织学结构观察

用光学显微镜对北草蜥(Takydromus septentrionalis)中脑视叶组织学结构进行了观察。视叶分为背侧的顶盖和腹侧的被盖,两者无明显界限。顶盖处灰质和白质交替排列。由表及里,可分为分子层、外灰质层、浅白质层、中灰质层、中白质层、深灰质层、深白质层和室管膜层。被盖处细胞层次不明显。在视叶的前部有横行的纤维将左右视叶联系起来。左右视叶室与中脑水管以及两视叶间的纵沟在视叶的中、后部相通。同时将北草蜥的中脑与其它低等脊椎动物进行了比较,推测北草蜥在进化上处于较低等地位。     

Morphology of the Mechanosensory Lateral Line System in Elasmobranch Fishes: Ecological and Behavioral Considerations

The relationship between morphology of the mechanosensory lateral line system and behavior is essentially unknown in elasmobranch fishes. Gross anatomy and spatial distribution of different peripheral lateral line components were examined in several batoids (Raja eglanteria, Narcine brasiliensis, Gymnura micrura, and Dasyatis sabina) and a bonnethead shark, Sphyrna tiburo, and are interpreted to infer possible behavioral functions for superficial neuromasts, canals, and vesicles of Savi in these species. Narcine brasiliensis has canals on the dorsal surface with 1 pore per tubule branch, lacks a ventral canal system, and has 8–10 vesicles of Savi in bilateral rows on the dorsal rostrum and numerous vesicles ( = 65 ± 6 SD per side) on the ventral rostrum. Raja eglanteria has superficial neuromasts in bilateral rows along the dorsal body midline and tail, a pair anterior to each endolymphatic pore, and a row of 5–6 between the infraorbital canal and eye. Raja eglanteria also has dorsal canals with 1 pore per tubule branch, pored and non-pored canals on the ventral surface, and lacks a ventral subpleural loop. Gymnura micrura has a pored dorsal canal system with extensive branch patterns, a pored ventral hyomandibular canal, and non-pored canal sections around the mouth. Dasyatis sabina has more canal pores on the dorsal body surface, but more canal neuromasts and greater diameter canals on the ventral surface. Sphyrna tiburo has primarily pored canals on both the dorsal and ventral surfaces of the head, as well as the posterior lateral line canal along the lateral body surface. Based upon these morphological data, pored canals on the dorsal body and tail of elasmobranchs are best positioned to detect water movements across the body surface generated by currents, predators, conspecifics, or distortions in the animal's flow field while swimming. In addition, pored canals on the ventral surface likely also detect water movements generated by prey. Superficial neuromasts are protected from stimulation caused by forward swimming motion by their position at the base of papillar grooves, and may detect water flow produced by currents, prey, predators, or conspecifics. Ventral non-pored canals and vesicles of Savi, which are found in benthic batoids, likely function as tactile or vibration receptors that encode displacements of the skin surface caused by prey, the substrate, or conspecifics. This mechanotactile mechanism is supported by the presence of compliant canal walls, neuromasts that are enclosed in wide diameter canals, and the presence of hair cells in neuromasts that are polarized both parallel to and nearly perpendicular to the canal axis in D. sabina. The mechanotactile, schooling, and mechanosensory parallel processing hypotheses are proposed as future directions to address the relationships between morphology and physiology of the mechanosensory lateral line system and behavior in elasmobranch fishes.     

A well defined spinocerebellar system in the weakly electric teleost fish Gnathonemus petersii. A tracing and immuno-histochemical study.

Long ascending fiber systems were investigated in the spinal cord of a teleost fish, Gnathonemus petersii. Concomitant results of Fink-Heimer degeneration tracing as well as CaBP28K immunohistochemical labelling demonstrate the existence of a well defined direct pathway from the very lowest spinal level to the caudal lobe of the cerebellum. HRP retrograde labelling shows that this pathway originates in a cellular column located in the most ventral part of the lateral column next to the lateral extremity of the ventral horn. From each spinal segment, the large axons of these cells gather and form a strip shaped tract at the periphery of the lateral column immediately dorsal to the cell column from which they originate. The spinal course of these fibers is ipsilateral; they give off a large number of collaterals to the lateral reticular nucleus. Bypassing the trigeminal motor nucleus, the lateral column tract courses dorsally to the paratrigeminal command associated nucleus between the lateral lemniscus and the nucleus preeminentialis and with a ventro-dorsally oriented large loop, turns in the caudal direction and penetrates into the cerebellar caudal lobe. Running caudally in the dorsal granular layer of the caudal lobe, it shifts more and more medially and crosses the midline whilst decussating with the contralateral tract on the dorsal margin of the molecular layer of the caudal lobe. Finally, the tract splits off and terminates throughout the granular layer of the caudal lobe. The main characteristics of this pathway are similar to those of the ventral spinocerebellar tract of higher vertebrates; it conveys information from all spinal levels directly to the contralateral cerebellum. However, it does not seem to receive direct synaptic input from the periphery, since projection of the dorsal root fibers appears to be limited to the dorsal ipsilateral half of the spinal cord. The appearance of such a pathway in a teleost fish is probably related to the existence of a well developed proprioceptive system in this species.     

Central representation of the anterior lateral line nerve in dwarf catfish]

The central distribution of the anterior lateral line nerve (ramus) (NLLa) were studied in the pygmean sheat-fish (Ictalurus nebulosus) by means of the method of Nauta--Gygax. NLLa, as well as posterior lateral line nerve (NLLp), projects topographically on the nucleus medialis of the acoustic-lateral area. Within the nucleus medialis NLLa can be traces in the rostro-lateral parts. A majority of NLLa fibres can be followed ipsilaterally, although a definite contralateral contribution also exists. It is concluded that NLLa, representing the electro- and mechanoreceptors of the head region, distributes predominantly within the rostral part of the medial nucleus, while NLLp, representing the trunk receptors, distributes in the caudal half of the medial nucleus. There is some overlapping within the middle part of the nucleus.     

Projection of cervical dorsal root fibers to the medulla oblongata in the brush-tailed possum, Trichosurus vulpecula

This study describes the projection of cervical spinal afferent nerve fibers to the medulla in the brush-tailed possum, a marsupial mammal. After single dorsal roots (between C2 and T1) were cut in a series of animals, the Fink-Heimer method was used to demonstrate the projection fields of fibers entering the CNS via specific dorsal roots. In the high cervical spinal cord, afferent fibers from each dorsal root form a discrete layer in the dorsal funiculus. The flattened laminae from upper cervical levels are lateral and those from lower cervical levels are medial within the dorsal columns. All afferent fibers at this level are separated from gray matter by the corticospinal fibers in the dorsal funiculus. All cervical roots project throughout most of the length of the well-developed main cuneate nucleus in a loosely segmentotopic fashion. Fibers from rostral roots enter more lateral parts of the nucleus, and fibers from lower levels pass to more medial areas; but terminal projection fields are typically large and overlap extensively. At more rostral medullary levels, fibers from all cervical dorsal roots also reach the external cuneate nucleus. The spatial arrangement here is more complex and more extensively overlapped than in the cuneate nucleus. Rostral cervical root fibers reach ventral and ventrolateral areas of the external cuneate nucleus and continue to its rostral pole; more caudal root fibers project to more dorsal and medial regions within the nucleus. These results demonstrate that projection patterns of spinal afferents in this marsupial are similar to those seen in the few placental species for which detailed data concerning this system are available.     

催产素、精氨酸加压素、促肾上腺皮质激素释放激素、神经肽Y、神经降压肽、P物质及亮氨酸脑啡肽免疫阳性纤维在大鼠结合臂旁核的分布

应用免疫细胞化学 ABC 技术观察了催产素、精氨酸加压素、促肾上腺皮质激素释放激素、神经肽 Y、神经降压肽、P 物质及亮氨酸脑啡肽免疫反应阳性纤维在大鼠结合臂旁核中的分布。催产素阳性纤维稀少,分布于腹外侧亚核、外外侧亚核、背外侧亚核及外外侧亚核与背外侧亚核之间的移行区。加压素阳性纤维亦甚为稀少,分布于腹外侧亚核、背外侧亚核、外外侧亚核与极外侧亚核.促肾上腺皮质激素释放激素阳性纤维分布于尾侧部臂旁核腰区、外外侧亚核腹内侧部、极外侧亚核、背外侧亚核、中央外侧亚核、内外侧亚核及臂旁内侧核。神经肽 Y 阳性纤维大多为串珠状的终末祥结构,分布于尾侧部腹外侧亚核、背外侧亚核、外外侧亚核背外侧部及外内侧亚核,在上外侧亚核、结合臂背内侧端背侧及臂旁内侧核腹侧部也有少量分布.神经降压肽阳性纤维分布于尾侧部臂旁核腰区、背外侧亚核、背外侧亚核与外外侧亚核之间的移行区、外外侧亚核、外内侧亚核及中吻部臂旁内侧核腹侧部。P 物质及亮氨酸脑啡肽阳性纤维分布于所有的臂旁外侧核诸亚核及外内侧亚核。     

The Neuroecology of the Elasmobranch Electrosensory World: Why Peripheral Morphology Shapes Behavior

The adaptations of elasmobranch sensory systems can be studied by linking the morphological structure with the natural behavior and ecology of the organism. This paper presents the first step in a neuroecological approach to interpret the spatial arrangement of the electrosensory ampullary organs in elasmobranch fishes. A brief review of the structure and function of the ampullae of Lorenzini is provided for interpretation of the organ system morphology in relation to the detection of dipole and uniform electric fields. The spatial projections of canals from discrete ampullary clusters were determined for the barndoor skate, Raja laevis, based upon a published figure in Raschi (1986), and measured directly from the head of the white shark, Carcharodon carcharias. The dorsoventrally flattened body of the skate restricts the projections of long canals to the horizontal plane. There is a distinct difference between dorsal and ventral projection patterns in all groups. Notable within-cluster features include a relatively long canal subgroup in the dorsal superficial ophthalmic (SOd) and dorsal hyoid (HYOd) clusters that are oriented parallel (bidirectionally) to the longitudinal axis of the body. It is postulated that this subgroup of canals may be important for detection and orientation to weak uniform fields. Ventral canal projections in the skate are primarily lateral, with the exception of the hyoid (HYOv) that also projects medially. This wide dispersion may function for the detection of prey located below the body and pectoral fins of the skate, and may also be used for orientation behavior. The mandibular canals located near the margin of the lower jaw (of both study species) are ideally positioned for use during prey manipulation or capture, and possibly for interspecific courtship or biting. The head of the white shark, which lacks the hyoid clusters, is ovoid in cross section and thus ampullary canals can project into three-dimensional space. The SOd and superficial ophthalmic ventral (SOv) clusters show strong rostral, dorsal and lateral projection components, whereas the SOv also detects rostral fields under the snout. In the sagittal plane, the SOv and SOd have robust dorsal projections as well as ventral in the SOv. Most notable are canal projections in the white shark buccal (BUC) ampullary cluster, which has a radial turnstile configuration on the ventrolateral side of the snout. The turnstile design and tilt between orthogonal planes indicates the white shark BUC may function in detection of uniform fields, including magnetically induced electric fields that may be used in orientation behaviors. These data can be used in future neuroecology behavioral performance experiments to (1) test for possible specializations of cluster groups to different natural electric stimuli, (2) the possibility of specialized canal subgroups within a cluster, and (3) test several models of navigation that argue for the use of geomagnetically induced electric cues.     

Distribution of the pulmonary artery and vein in the chimpanzee lung

Lungs of two chimpanzees (Pan troglodytes) were examined. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole and, then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal bronchiole system and the lateral bronchiole system, along the right bronchus. During its course, it gives off arterial branches which run along each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole and then between the dorsal bronchiole system and the lateral bronchiole system. The branches of the pulmonary artery run mainly along the dorsal or lateral side of the bronchiole. The pulmonary veins run mainly along the ventral or medial side of the bronchioles, and between them. Finally, they enter the left atrium with four large veins, i.e. the common trunk of the right upper lobe vein and the right middle lobe vein, right lower lobe pulmonary venous trunk, left middle lobe vein, and left lower lobe pulmonary venous trunk.     

Immunohistochemical mapping of galanin-like neurons in the rat central nervous system

Using an antiserum generated in rabbits against synthetic galanin (GA) and the indirect immunofluorescence method, the distribution of GA-like immunoreactive cell bodies and nerve fibers was studied in the rat central nervous system (CNS) and a detailed stereotaxic atlas of GA-like neurons was prepared. GA-like immunoreactivity was widely distributed in the rat CNS. Appreciable numbers of GA-positive cell bodies were observed in the rostral cingulate and medial prefrontal cortex, the nucleus interstitialis striae terminalis, the caudate, medial preoptic, preoptic periventricular, and preoptic suprachiasmatic nuclei, the medial forebrain bundle, the supraoptic, the hypothalamic periventricular, the paraventricular, the arcuate, dorsomedial, perifornical, thalamic periventricular, anterior dorsal and lateral thalamic nuclei, medial and central amygdaloid nuclei, dorsal and ventral premamillary nuclei, at the base of the hypothalamus, in the central gray matter, the hippocampus, the dorsal and caudoventral raphe nuclei, the interpeduncular nucleus, the locus coeruleus, ventral parabrachial, solitarii and commissuralis nuclei, in the A1, C1 and A4 catechaolamine areas, the posterior area postrema and the trigeminal and dorsal root ganglia. Fibers were generally seen where cell bodies were observed. Very dense fiber bundles were noted in the septohypothalamic tract, the preoptic area, in the hypothalamus, the habenula and the thalamic periventricular nucleus, in the ventral hippocampus, parts of the reticular formation, in the locus coeruleus, the dorsal parabrachial area, the nucleus and tract of the spinal trigeminal area and the substantia gelatinosa, the superficial layers of the spinal cord and the posterior lobe of the pituitary. The localization of the GA-like immunoreactivity in the locus coeruleus suggests a partial coexistence with catecholaminergic neurons as well as a possible involvement of the GA-like peptide in a neuroregulatory role.     

The development of GABA-like immunoreactivity in the thoracic ganglia of the locust Schistocerca gregaria

Summary The development of GABA-like immunoreactivity was investigated in embryonic and juvenile locusts using an antibody raised against GABA-protein conjugates. GABA-like immunoreactivity was first detectable in the neuropile of embryonic ganglia at 55% development, and in neuronal somata at 62% development. The total number of immunoreactive somata increased between 62% and 85% embryonic development, and followed an anterio-posterior pattern of expression. At 85% development, the number of immunoreactive somata reached adult levels and no change in number was then seen. In embryonic stages and first and second juvenile instars two dorsal and four ventral groups of somata were labeled in all three thoracic ganglia, whilst in later juvenile instars one of the dorsal groups was visible as a separate entity only in the metathoracic ganglion. These early patterns were modified by alterations in the positions of some of the groups during late embryogenesis and during juvenile development to produce the adult pattern. The results show that the development of GABA expression is similar to that of other neurotransmitters. The characteristics of the development of immunoreactivity indicate that some of these immunoreactive clusters may be derived from clonally related neurones. Finally, we demonstrate the presence of immunoreactive somata and processes in embryos, which correspond to those of identified local and intersegmental interneurones studied in the adult.Abbreviations Ab1–3 first-third abdominal ganglion - CON connective - CI _1–3 common inhibitors 1–3 - CTC tract - DC I–VII dorsal commissures I–VII - DIT dorsal intermediate tract - DMT dorsal median tract - LDT lateral dorsal tract - LF lateral fibres - o, iLVT outer and inner lateral ventral tract - MVT median ventral tract - N1–5 nerves 1–5 - aPT anterior perpendicular tract - PT perpendicular tract - aRT anterior ring tract - R1–5 nerve roots 1–5 - PVC posterior ventral commissure - SMC supra-median commissure - T3 metathoracic neuromere - TT T tract - aVAC anterior ventral association centre - VC I ventral commissure I - d,vVCII dorsal and ventral parts of ventral commissure II - VF ventral fibres - VIT ventral intermediate tract - VLT ventral lateral tract - VMT ventral median tract - (d,v)LAG (dorsal and ventral) lateral anterior group - LDG lateral dorsal group - LVG lateral ventral group - MDG medial dorsal group - MPG medial posterior group - MVG medial ventral group     

Cortical neurons projecting to the posterior part of the superior temporal sulcus with particular reference to the posterior association area. An HRP study in the monkey

Corticocortical connections from the posterior association area to the posterior part of the superior temporal sulcal cortex (STs area) were studied in the monkey by means of retrograde axonal transport of horseradish peroxidase (HRP) or wheatgerm-agglutinin-conjugated HRP (WGA-HRP). After injecting 0.05-0.2 microliter of 50% HRP or 5% WGA-HRP into the STs area, labeled cells were examined in various cortical regions. The dorsal wall of the STs receives fibers mainly from the inferior parietal lobule (area 7) and superior temporal gyrus (area 22), whereas the ventral wall and floor part of the STs receive fibers from the posterior inferotemporal gyrus (area TEO) and prestriate cortex (areas 18 and 19). The deeper parts of the dorsal wall close to the floor region of the STs area also receive many fibers from the cortical walls surrounding the intraparietal, lunate and lateral sulci. Both the dorsal and ventral cortical walls of the intraparietal sulcus send fibers mainly to the deep dorsal wall of the STs. The ventral wall of the STs, on the other hand, receives fibers only from the ventral wall of the intraparietal sulcus. The medial surface of the prestriate cortex and the parahippocampal region send fibers to both walls of the STs. In the prestriate-STs projections originating from areas around the parieto-occipital sulcus, a topographic correlation is present; area 19 located anterior to the sulcus projects to the dorsal wall, whereas area 18 situated posterior to the sulcus projects to the ventral wall. Only the dorsal wall receives fibers from the cingulate (areas 23 and 24) and subparietal gyri (area 7). The deeper part of the dorsal wall and the ventral wall of the posterior STs area are interconnected with each other, while the upper part of the dorsal wall does not appear to receive fibers from the ventral wall.     

The bronchial tree,lobular division,and blood vessels of the lung of the Diana monkey (Cercopithecus diana)

The authors examined the lung of one Diana monkey (Cercopithecus diana). The right lung consists of upper, middle, lower, and accessory lobes, the upper and middle lobes being united dorsally. The accessory and lower lobes are separated from the other lobes by fissures. The left lung consists of a bi-lobed middle lobe and a lower lobe. These lobes are separated by an interlobular fissure. The Diana monkey has dorsal, lateral, ventral, and medial bronchiole systems on either side. The upper lobe is formed by the first bronchiole of the dorsal bronchiole system. The middle lobe is formed by the first bronchiole of the lateral bronchiole system and the accessory lobe is formed by the first bronchiole of the ventral bronchiole system. The remaining bronchioles of the four bronchiole systems constitute the lower lobe. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal and lateral bronchiole systems, along the dorso-lateral side of the right bronchus. During its course, the right pulmonary artery gives off arterial branches running along the dorsal or lateral side of each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole. Thereafter, it follows the same course as in the right lung, giving off arterial branches. The pulmonary veins run along the ventral or medial side of the bronchiole, and between the bronchioles.     

Functional morphology of the cephalopod buccal mass: a novel joint type

The arrangement of the musculature and connective tissues of the buccal mass of the coleoid cephalopods Octopus bimaculoides, Sepia officinalis, and Loliguncula brevis was examined using dissection and histology. Serial sections in three mutually perpendicular planes were used to identify the muscles and connective tissues responsible for beak movements and stability and to describe their morphology and fiber trajectories. Four major beak muscles were identified: the anterior, posterior, superior, and lateral mandibular muscles. The anterior, posterior, and superior mandibular muscles connect the upper beak and the lower beak. Although the lateral mandibular muscles originate on the upper beak, they do not connect to the lower beak and instead insert on a connective tissue sheath surrounding the buccal mass. Examination of the fibers of the lateral mandibular muscles reveals that they have the organization of a muscular hydrostat, with muscle fibers oriented in three mutually perpendicular orientations. Although the beaks are capable of complex opening, closing, and shearing movements, they do not contact one another and are instead connected only by the musculature of the buccal mass. Based on the morphological analysis and observations of freshly dissected beaks undergoing the stereotyped bite cycle, the functional role of the beak muscles is hypothesized. The anterior and superior mandibular muscles are likely responsible for beak closing and shearing movements. The posterior mandibular muscle is likely also involved in beak closing, but may act synergistically with the lateral mandibular muscles to open the beaks. The lateral mandibular muscles may use a muscular-hydrostatic mechanism to control the location of the pivot between the beaks and to generate the force required for beak opening. The lack of contact between the beaks and the morphology of the lateral mandibular muscles suggests that the buccal mass of coleoid cephalopods may represent a previously unexamined flexible joint mechanism. The term "muscle articulation" is proposed here to denote the importance of the musculature in the function of such a joint.