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1.
Juvenile and young adult specimens ofCarcinus maenas were kept in the laboratory under controlled conditions. The main organic constituents and their variations during the molt cycle were quantitatively determined.
1.  During postmolt the chitin concentration rises rapidly (20–74 mg/g dry weight) in parallel to the dry weight (120–293 mg/g fresh weight). Both decrease again before ecdysis (Fig. 1).
2.  The glycose level in the hemolymph (50–80 g/ml) shows no significant variation during the molt cycle (Fig. 2).
3.  The glycogen concentrations in integument, (14–180 mg/g dry weight), gills (5.5–66 mg/g dry weight), muscle (8.8–41 mg/g dry weight), heart (135–308 mg/g dry weight) and hemolymph (160–690 g/ml) reach their maximum values during the premolt stage. The highest glycogen content in the midgut gland (83 mg/g dry weight) is observed immediately before and after ecdysis. Glycogen storage in heart and hemolymph, can, account for about half of the glycogen stored in the midgut gland (Figs. 3,4 and 5).
4.  The lipid concentration in the hemolymph (120–440 g/ml) and in gills (33.6–70 mg/g dry weight) rises during the premolt stage (Figs. 6 and 7).
5.  The protein concentration in the hemolymph increased during premolt (9–31 mg/ml). The copper content (13–42 g/ml) varies in parallel to the protein concentration indicating that the proportion of hemocyanin to total proteins remains constant during the molting cycle (Fig. 8).
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2.
1.  The larva of the tiger beetle (Cicindela chinensis) possesses six stemmata on either side of the head. Optical and physiological properties of two pairs of large stemmata and a pair of anterior medium sized stemmata, and responses of second-order visual interneurons (medulla neurons) have been examined.
2.  Objects at infinite distance were estimated to focus 50 m deep in the retina in the large stemmata. Receptive fields of four large stemmata, the acceptance angle of each being 90°, largely overlapped one another.
3.  The stemmata possessed a single type of retinular cell with a maximal spectral sensitivity at 525 nm, and a flicker fusion frequency of 25–50 Hz.
4.  Medulla neurons expanded fan-shaped dendrites in the medulla neuropil, and their axons extended into the protocerebrum. They responded to illumination with a variety of discharge patterns. They also responded with spike discharges to moving objects and to apparent movements provided by sequential illumination or extinction of LEDs. They did not show directional selectivity. They possessed well-defined receptive fields ranging from 30° to 105°.
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3.
1.  The ecdysial growth of cercal filiform hairs was investigated in the cricketGryllus bimaculatus. The length of hairs varied from 40 to 500 m in the 1st, from 40 to 650 m in the 3rd and from 30 to 800 m in the 5th instar nymphs (Fig. 1). Hemimetabolous development causes both hair growth and the appearance of new hairs at each ecdysis (Figs. 2, 3). The newly acquired hairs were shorter than 200 m in every case (Fig. 4).
2.  Velocity thresholds of cercal sensory interneurons (CSIs) to sinusoidal air-currents were measured in 3rd instar nymphs (Fig. 5 A, B, C). CSIs 8-1 (medial giant interneuron: MGI) and 9-1 (lateral giant interneuron: LGI) showed threshold curves of acceleration sensitivity similar to those in adults. The thresholds for CSIs 8-1 and 9-1 were on the average higher in nymphs than in adults. The threshold curves for the two velocity-sensitive CSIs 10-2 and 10-3 were similar for nymphs and adults.
3.  Velocity thresholds of cercal filiform sensilla were measured in 3rd instar nymphs (Fig. 6). In spite of the small size of nymphal hairs, the most sensitive ones showed the same sensitivity as did the long 1000 m hairs of the adult.
4.  The filiform hairs in 3rd instar nymphs were supported by a weaker spring than in adults (Fig. 7). Relative stiffness was about 50% of that in the long hairs in adults, but not much different than that in the short hairs.
5.  Based on a theoretical estimation of hair motion, the threshold angle of a filiform sensillum in the 3rd instar nymph was calculated (Fig. 9). Threshold angles of the long sensilla seemed to be unchanged throughout hemimetabolous development.
This paper is dedicated to the memory of the late professor Hiroshi Ikeda, Biological Institute, Faculty of General Education, Ehime University, Matsuyama, Japan  相似文献   

4.
1.  Echolocating bats (Eptesicus fuscus) were trained to discriminate between simulated targets consisting of one or two echo-wavefronts with internal time delays of up to 100 s. Spectral and temporal properties and total signal energy of the targets were evaluated and predictions for performances of bats derived from receiver models were compared with measured performances.
2.  Eptesicus fuscus was able to discriminate a one-wavefront target from two-wavefront targets with distinct internal time delays (12 s, 32–40 s and 52–100 s). Performance was not affected by changes in total signal energy. Bats also successfully discriminated between two-wavefront targets with different internal time delays.
3.  Performance predicted from differences in total energy between targets did not match the measured performance, indicating that bats did not rely on total echo energy. This finding is also supported by the behavioral data. Performance predicted from spectral and temporal receiver models both matched the measured performance and, therefore, neither one of these models can be favored over the other.
4.  The behavioral data suggest that Eptesicus fuscus did not transform echo information into estimates of target range separation and, therefore, did not perceive the two wavefronts of each simulated two-wavefront echo as two separate targets.
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5.
1.  Paramecium bursaria was stimulated by a light spot of 10–15 m diameter, and the photosensitive site was searched by recording responses in swimming behavior and in membrane potential.
2.  Local stimulation to the anterior half of the cell caused an avoiding response.
3.  Stimulation to the cells deciliated by ethanol treatment elicited a depolarization of the membrane potential.
4.  Local stimulation to the anteroventral portion elicited a depolarization, but stimulation to the dorsal side induced no change in the membrane potential.
5.  The action spectrum of depolarization elicited by local stimulation to the anteroventral surface showed two main peaks at 420 nm and 560 nm, corresponding to those of light stimulation of the whole cell.
6.  It is concluded that a photosensitive site exists on the anteroventral surface ofParamecium, in particular within the oral groove of the cell. This local photosensitivity is discussed with respect to the mating reaction.
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6.
1.  Non-visual sensory systems are likely to be important in antarctic fish since these fish inhabit an area where low light levels occur for long periods. This study was undertaken to examine the suitability of the lateral line system for prey detection.
2.  Recordings were made from afferent fibres of the anterior lateral line in the antarctic fishPagothenia borchgrevinki.
3.  A vibrating probe was used to stimulate the lateral line at a range of frequencies between 10 and 100 Hz.
4.  Most units responded best at a stimulus frequency of 40 Hz. Below the best frequency the response typically declined steeply and at higher frequencies it was usually better sustained.
5.  Crustacea identified as major components of the diet ofPagothenia borchgrevinki were individually attached to a force transducer to determine the vibrations produced by swimming movements.
6.  The Fourier amplitude spectra of swimming crustaceans exhibited prominent low frequency peaks at 3–6 Hz and higher frequency peaks in the 30–40 Hz range.
7.  It is concluded that the overlap in the frequency response characteristics of the anterior lateral line and the frequencies produced by crustacean prey clearly establishes the suitability of the lateral line for prey detection.
8.  In several instances recordings were made from fish primary afferent neurons responding to a swimming amphipod. These recordings confirm that crustacean swimming is indeed a potent natural stimulus of the lateral line system.
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7.
1.  The physiology and morphology of olfactory interneurons in the brain of larval Manduca sexta were studied using intracellular recording and staining techniques. Antennal olfactory receptors were stimulated with volatile substances from plants and with pure odorants. Neurons responding to the stimuli were investigated further to reveal their response specificities, dose-response characteristics, and morphology.
2.  We found no evidence of specific labeled-lines among the odor-responsive interneurons, as none responded exclusively to one plant odor or pure odorant; most olfactory interneurons were broadly tuned in their response spectra. This finding is consistent with an across-fiber pattern of odor coding.
3.  Mechanosensory and olfactory information are integrated at early stages of central processing, appearing in the responses of some local interneurons restricted to the primary olfactory nucleus in the brain, the larval antennal center (LAC).
4.  The responses of LAC projection neurons and higher-order protocerebral interneurons to a given odor were more consistent than the responses of LAC local interneurons.
5.  The LAC appears to be functionally subdivided, as both local and projection neurons had arborizations in specific parts of the LAC, but none had dendrites throughout the LAC.
6.  The mushroom bodies and the lateral protocerebrum contain neurons that respond to olfactory stimulation.
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8.
1.  Some units in the lateral ocellar nerves of the locust,Locusta migratoria, are influenced transsynaptically by the activity of ascending fibres in the thoracic connectives and therefore may be efferent to the afferent ocellar system.
2.  A variety of sensory inputs excite the ocellar nerve units, including illumination of the compound eyes, active and passive movement of the wings, wind stimuli to the thorax and sound.
3.  Most ocellar interneurons are influenced transsynaptically by electrical stimulation of the cervical connectives. L-neurons are depolarized and the components of their response to a rectangular light pulse are changed in amplitude. Only a few S-neurons could be examined. All of them were excited directly or indirectly.
4.  The descending ocellar interneurons (DN's) are influenced by stimulation of the contralateral connective, perhaps via efference to the ocellus or to ocellar L-cells.
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9.
The role of Juvenile Hormone III in phonotaxis, mating behavior and egg production of cricket females from Gryllus campestris, Gryllus bimaculatus, Teleogryllus commodus, and Acheta domesticus was investigated.
1.  Phonotaxis of crickets was measured on a Kramer spherical treadmill by means of an infrared system which allowed free walking at any speed and direction. Crickets were allatectomized during the adult or last nymphal stage, and the controls sham-operated. On each cricket, 2 to 9 phonotactic tests were performed during a period of 12 to 51 days; the allatectomized nymphs were tested as adults.
2.  All females deprived of their corpora allata during the adult stage continued to exhibit phonotaxis, whereas females operated as nymphs developed and maintained phonotaxis (Tables 1–4). Some of these females allatectomized or sham-operated during the adult or nymphal stage exhibited correct phonotactic behavior as well as undirected walking.
3.  At the end of the test series, all allatectomized females were found to be devoid of Juvenile Hormone, whereas the controls varied according to age from 0.2 to 2.0 pmol/10 l. The individual ecdysteroid levels differed unpredictably in allatectomized and control females (0.02 to 6.4 pmol/10 l), and no correlation was found between the number of eggs produced by allatectomized females and their ecdysteroid titer.
4.  All allatectomized females displayed sexual receptivity.
5.  Adults allatectomized during the last nymphal instar were still able as adults to develop single eggs in G. campestris and G. bimaculatus, while females of T. commodus did produce and store moderate numbers. However, in A. domesticus no eggs were produced, and terminal oocytes had reached 0.5 to 0.7 mm in length, which is the previtellogenic size of terminal oocytes in normal females at the age of one to two days.
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10.
Müller  D. G.  Frenzer  K. 《Hydrobiologia》1993,(1):37-44
Culture studies with healthy and virus-infected isolates of Ectocarpus siliculosus, Feldmannia simplex and F. irregularis gave the following results:
–  Virus particles are produced in deformed reproductive organs (sporangia or gametangia) of the hosts and are released into the surrounding seawater.
–  Their infective potential is lost after several days of storage under laboratory conditions.
–  New infections occur when gametes or spores of the host get in contact with virus particles. The virus genome enters all cells of the developing new plant via mitosis.
–  Virus expression is variable, and in many cases the viability of the host is not impaired. Infected host plants may be partly fertile and pass the infection to their daughter plants.
–  Meiosis of the host can eliminate the virus genome and generate healthy progeny.
–  The genome of the Ectocarpus virus consists of dsDNA. Meiotic segregation patterns suggest an intimate association between virus genome and host chromosomes.
–  An extra-generic host range has been demonstrated for the Ectocarpus virus.
–  Field observations suggest that virus infections in ectocarpalean algae occur on all coasts of the world, and many or all Ectocarpus and Feldmannia populations are subject to contact with virus genomes.
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11.
1.  The specificity and sensitivity of the olfactory organ of adult zebrafish, Danio rerio, to selected amino acid, bile acid, and steroid odorants were characterized using the electro-olfactogram recording technique. The olfactory organ was responsive to 28 of the 29 odorants tested.
2.  All of the 100 M amino acid and bile acid stimulants elicited a negative-going response that was significantly greater than the response to the artificial freshwater control. The general pattern of relative stimulatory effectiveness established for the amino acid stimuli was neutral amino acids > basic amino acids > acidic amino acids > imino acids. The general pattern of relative stimulatory effectiveness of 100 M bile acid stimuli was taurine-conjugated bile acids > glycineconjugated bile acids non-conjugated bile acids. The responses to the most stimulatory bile acid odorants were up to 40% larger than the responses to the most stimulatory amino acid odorants.
3.  The response threshold for cysteine and taurocholic acid, the most stimulatory of the amino acid and bile acid stimuli tested, was approximately 10-8 M. Females are significantly more sensitive to these odorants than males.
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12.
1.  We studied the response of plurisegmental interneurons in the suboesophageal ganglionic mass of female spiders (Cupiennius salei) to male vibratory courtship signals.
2.  The opisthosomal vibrations (low frequency component) and the pedipalpal percussions (high frequency component) are processed in parallel by interneuron type I and type II, respectively (Figs. 3, 7).
3.  Type III, IV and V interneurons represent the macrostructure of the male courtship signals (Figs. 8, 9, 10), i.e. the beginning and the end of a series (type III, V) or the end of the series only (type IV). The macrostructure is known to influence the response probability of the female. The spontaneous bursting activity of a type VI neuron undergoes slow and long lasting changes upon stimulation with natural courtship signals (Fig. 11).
4.  Many interneurons responded to natural signals but not to behaviourally effective computer models. This is presumably due to the lack of spectral complexity of the model compared to natural signals. Differences in the natural conspecific and heterospecific signals, however, are represented by the neuronal response (Fig. 3).
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13.
1.  In the tortoise the capability of the spinal cord of generating rhythmic motor activity and of modulating reflex transmission depending on the motor cycle was investigated.
2.  In the intact animal co-ordinated locomotion was only observed if the feet had ground contact. Without ground contact only rhythmic struggling movements occurred. After spinalization some peripheral input was needed to initiate and sustain struggling movements in the air; the pattern of the movements was changed but not the frequency. After paralyzation the capability of generating a rhythmic activity was distinctly depressed in the spinal tortoise. The frequency of a rhythmic activity which could be induced in such a preparation by peripheral stimulation was very low, even after premedication with nialamide and DOPA.
3.  In the spinal paralyzed preparation during rhythmic motor activity a modulation of the membrane potential of motoneurones occurred with phases of depolarization and hyperpolarization. The latter at least partly were due to synaptic inhibition.
4.  In the spinal paralyzed preparation the transmission in excitatory reflex pathways from peripheral flexor reflex afferents (FRA) to motoneurones was phasically modulated during rhythmic motor activity in the way that the transmission was facilitated during the active phase of a motoneurone pool and inhibited during the reciprocal phase. In the inhibitory FRA pathways partly a particular kind of modulation of the transmission during the different phases was observed.
5.  The results indicate that the rhythmic motor activity in the spinal paralyzed tortoise which largely matched the activity found in cats, resembles in some aspects locomotor activity and therefore by analogy with findings in cats and turtles may be denoted as fictive locomotion.
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14.
1.  Up to 9 kHz, the tympanal membrane of the grasshopper Chorthippus biguttulus responds with equal sensitivity at the attachment sites of the low and the high-frequency receptors; at the latter site it is also particularly sensitive between 10 and 20 kHz.
2.  The frequency spectra of the songs of both sexes exhibit maxima at 7–8 kHz, to which the membrane is well matched. In the high-frequency region, where the male songs have a peak at 30 kHz, there is no corresponding maximum in the membrane oscillation.
3.  Because the tympanal membrane is immediately adjacent to air sacs in the tracheal system, it is deflected inward and outward by as much as 80 m during the respiratory cycle.
4.  Measurements by laser vibrometry show that acoustically induced membrane oscillations are attenuated severely due to the respiratory displacement of the membrane for frequencies up to 10–12 kHz. By contrast, at higher frequencies the membrane sensitivity is doubled or tripled.
5.  As a result of these membrane effects, the discharge in the tympanal nerve was profoundly reduced in the low-frequency range, whereas above 11 kHz there was a marked increase. This modulation of auditory sensitivity affects the animals' ability to detect conspecific songs.
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15.
Several species of weakly electric fish reflexively change their frequency of electric organ discharge (EOD) in response to sensing signals of similar frequency from conspecifics; that is, they exhibit jamming avoidance responses (JAR).Eigenmannia increases its EOD frequency if jammed by a signal of lower frequency and decreases its EOD frequency if jammed by a signal of higher frequency. This discrimination is based on an analysis of the patterns of amplitude modulations and phase differences resulting from signal interference. Fish of the closely related genus,Sternopygus, however, do not exhibit a JAR. Here we show that despite lacking this behavior,Sternopygus shares many sensory processing capacities withEigenmannia:
1.  Fish could be conditioned to discriminate the sign of the frequency difference (Df) between an exogenous sinusoidal signal and its own EODs with as few as 300 training trials.
2.  Fish can discriminate the sign of Df for jamming signals with an amplitude as low as 2 V/cm (p-p); which is approximately 40 dB below the amplitude of the fish's EOD, as measured lateral to the operculum.
3.  Fish appear to discriminate the sign of Df by evaluating modulations in signal amplitude and differences in the timing of signals received by different areas of the body surface.
4.  Sternopygus processes electrosensory information through band-pass modulation filters. Tuning to modulation rates over at least 4–16 Hz exists.
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16.
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17.
1.  We have investigated a physiological component of the gravitaxis of Paramecium using established mechanisms of ciliate mechanosensitivity. The horizontal, up and down swimming rates of cells, and the sedimentation of immobilized specimens were determined. Weak DC voltage gradients were applied to predetermine the Paramecium swimming direction.
2.  An observed steady swimming rate is the vector sum of active propulsion (P), a possible gravity-dependent change in swimming rate (), and rate of sedimentation (S). We approximated P from horizontal swimming. S was measured after cell immobilization.
3.  Theory predicts that the difference between the down and up swimming rates, divided by two, equals the sum of S and . is supposed to be the arithmetic mean of two subcomponents, a and p, from gravistimulation of the anterior and posterior cell ends, respectively.
4.  A negative value of (0.038 mm/s) was isolated with a(0.070 mm/s) subtracting from downward swimming, and p(0.005 mm/s) adding to upward propulsion. The data agree with one out of three possible ways of gravisensory transduction: outward deformation of the mechanically sensitive lower soma membrane. We call the response a negative gravikinesis because both a and p antagonize sedimentation.
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18.
The content of neuraminic acid (NA) of different developmental stages of trout eggs was determined.
1.  The total NA increases from about 13 g NA per egg (6–8 weeks before spawning) to 50 g directly before spawning until hatching.
2.  In freshly hatched fish larvae the NA-content is decreased to about 40 per cent as compared with stages before hatching.
3.  The ratio of bound to free NA decreases from values of about 13.5 (6–8 weeks before spawning) to 0.85–1.2 at the hatching-stage.
4.  The bound NA is almost entirely bound to sialo-glycoproteins.
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19.
1.  The oscillations of the tympanal membrane of Locusta migratoria were analysed by combined laser vibrometry and interferometry. Simultaneously the activity in the tympanal nerve was recorded extracellularly. The animal was stimulated by sound pulses and one of the hindlegs was passively moved in a sinusoidal manner simulating stridulation. These stimuli were applied separately and in combination.
2.  Sound stimulation elicited high-frequency membrane oscillations, whereas leg movements induced slow rhythmic membrane displacements. During combined sound and movement stimulation these two types of oscillations superimposed without mutual interference.
3.  The tympanal nerve responded to sound with well synchronized receptor activity. The leg movement elicited less synchronized, phase-coupled activity. During combined sound and movement stimulation the responses to the two types of stimuli interfered strongly.
4.  The activity patterns of single receptor fibres and auditory interneurons were reanalysed from this point of view. The extent of synchronization of the receptors is found to be the major difference between the sound-induced and the movement-induced activation of the auditory system. A filter mechanism is postulated, consisting in the activation of some higher order auditory interneurons only by well-synchronized presynaptic activity, such as is induced by steeply rising sound pulses.
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20.
1.  Coordinated movements of the wings during flight in the locust result from coordinated activity of flight neurons in the thoracic ganglia. Many flight interneurons and motoneurons fire synchronous bursts of action potentials during the expression of the flight motor pattern. The mechanisms which underlie this synchronous firing were investigated in a deafferented preparation of Locusta migratoria.
2.  Simultaneous intracellular recordings were taken from flight neurons in the mesothoracic ganglion using glass microelectrodes filled with fluorescent dye.
3.  Three levels of synchronous activity between synergistic motoneurons and between the right and left partners of bilaterally symmetrical pairs of interneurons were observed: bursting which was loosely in phase but which showed little correlation between the temporal parameters of individual bursts in the two neurons; bursting which showed synchrony of the beginning and end of bursts; and bursts which showed highly synchronous spike-for-spike activity.
4.  Direct interactions between the neurons had little or no part to play in maintaining any of the levels of synchrony, even in instances of very close synchrony (spikes in different neurons occurring within 1 ms of each other). Highly synchronous firing was a consequence of common synaptic input impinging on neurons with similar morphological and physiological properties.
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