BOSTONIA PERPLEXA GEN. ET SP. NOV., A CALAMOPITYAN AXIS FROM THE NEW ALBANY SHALE OF KENTUCKY

Bostonia perplexa, gen. et sp. nov., was collected from the Lower Mississippian Falling Run member of the Sanderson Formation. The single short segment of an axis, preserved as a petrifaction, contains at least three vascular columns, each with both primary and secondary tissues. Primary xylem is two or three ribbed, and contains several mesarch protoxylem strands. Gymnospermous secondary xylem is characterized by both uniseriate and multiseriate rays. The ground tissue is parenchymatous except for a few clusters of sclerotic cells. In its apparent polystelic nature, the specimen superficially resembles members of the Pennsylvanian to Permian Medullosaceae. All evidence currently available, however, leads to the conclusion that this species should be placed in the Upper Devonian to Lower Mississippian Calamopityaceae. It has not been determined with certainty whether the species is polystelic (in the sense of the Medullosaceae), or whether the apparent polystely is the result of stelar branching proximal to the level of branch divergence.     

ZHAOTONGASPIS JANVIERI GEN.ET SP.NOV.,A GALEASPID FROM EARLY DEVONIAN OF ZHAOTONG,NORTHEASTERN YUNNAN

ThefirstearlyvertebratedescribedfromtheDevonianofZhaotong,northeast-ernYunnan(Fig.i),wasthegaleaspidSanqiaspiszhaotongensis(Liu,i975).Thefish-b6aringhorizonwasthoughttobelongtotheCuifengshanFormation,thatis,Pragianinage,incomparisonwiththetypelocalityofthisformationintheQujingdistrict,Yunnan.Liaoctal.(l978)consideredthatitwouldbemoreappro-priatetonametheh0riz0nasthePosongchongFormation,sinceithasthesamelitho1ogyandfaunaastheP0s0ngchongFormationintheWenshandistrict,Yunnan.Thissuggesti0…     

ATRACTOMORPHA ECHINATA GEN. ET SP. NOV., A NEW ANISOGAMOUS MEMBER OF THE SPHAEROPLEACEAE (CHLOROPHYCEAE)1,2

Atractomorpha echinata gen. et sp. nov. is described from isolates derived from zygotes present in a dry soil sample obtained from Texas. The new genus is distinguished from Sphaeroplea primarily by its pattern of vegetative growth. While Sphaeroplea is distinctly filamentous with numerous coenocytic cells uniseriately arranged, Atractomorpha grows as individual, multinucleate, spindle-shaped cells with sharply pointed extremities. Such cells may vary considerably in length (25–6000 μm, or more) and normally lack septa. In young, rapidly growing cultures the cells often attain lengths of 300–500 μm, but rarely exceed 1800 μm. The new species is further characterized by: (1) the regular formation of biflagellate zoospores in asexual reproduction, (2)anisogamy (occasionally oogamy) and (3) the size and ornamentation of its zygotes. Variations in vegetative morphology are discussed as are conditions for obtaining gametogenesis.     

A NEW SPECIES OF MARSILEA FROM THE DAKOTA FORMATION IN CENTRAL KANSAS

Discovery of compression/impression megafossil material from the Cenomanian (mid-Cretaceous) in Kansas documents the occurrence of the genus Marsilea during this age. Only vegetative material has been found as complete plants; associated structures that may be fertile structures could belong to the genus also. This new fossil species extends the megafossil record of the genus back to the mid-Cretaceous when previously only megaspores attributed to the family occurred during this time. The fossil record of the heterosporous aquatic fern families is reviewed with emphasis on the Marsileaceae.     

VALLITHECA VALENTIA GEN. ET SP. NOV., PERMINERALIZED SYNANGIA FROM THE MIDDLE PENNSYLVANIAN OF OKLAHOMA

Vallitheca valentia gen. et sp. nov. is a permineralized, synangiate fructification of probable seed fern affinities from the Wewoka Formation (Desmoinesian) near Ada, Oklahoma. Synangia are oblong to pyriform, average 1 cm long, and contain 32 to 48 tubular sporangia embedded proximally in ground tissue. The sporangia are arranged within the synangia in a unique pattern: a ring of peripheral sporangia dehisces toward the center of the synangium and a central group of sporangia dehisces outward. This unique arrangement is unlike that of any currently recognized group.     

ARCHAEOLEERSIA NEBRASKENSIS GEN. ET SP. NOV. (GRAMINEAE-ORYZEAE), A NEW FOSSIL GRASS FROM THE LATE TERTIARY OF NEBRASKA

Archaeoleersia nebraskensis, gen. et sp. nov. was collected from the Late Miocene Ash Hollow Formation in Garden County, Nebraska. The remains consist of anthoecia (fertile lemmas and paleas) preserved as silicifications. Examination of anthoecia by scanning electron microscopy revealed prickle hairs, simple projections, and microhairs. The fossils compare most closely with living Leersia ligularis Trin. of Central and South America. Archaeoleersia nebraskensis resembles more southern living taxa and suggests that climatic deterioration during the Late Tertiary or Quaternary resulted either in a southward migration of ancestral North American forms or in the elimination of North American populations of already widely distributed ancestral forms. Associated flora and fauna indicate a mesic, lacustrine paleoenvironment for Archaeoleersia nebraskensis.     

NEW DISCOVERY OF YUNNANOLEPIDS- HETEROYUN-NANOLEPIS QUJINCENSIS (GEN. ET SP. NOV.)

Thenewformdiffersfromtlieotheryunnanolepidsinthefollowingcharacteristics:1)orbitalfenestrabiggerandinamoreanteriorposition;2)possessingpreorbitalrecess(prh)insteadofpreorbitaldepression;3)infraorbitalsensorycanalpassingthroughpostmarginalplate;supraorbitalsensorycanalonpost-pinealplate;4)posteriorinternaltransversecrestinamoreposteriorposition.Onthebasisofcharactersofthenewgenus,thefollowingconcludingremarksarepreliminarygiven:1)Thepreorbitaldepressioninyunnanolepidsisprobab1ynothomologouswith…     

LEACHIELLA PACIFICA,GEN. ET SP. NOV., A NEW PARASITIC RED ALGA FROM WASHINGTON AND CALIFORNIA

Leachiella pacifica, gen. et sp. nov., a marine alloparasitic red alga is described from Washington and California. Several species of Polysiphonia and Pterosiphonia are hosts for this parasite. The thallus is a white, multiaxial, unbranched pustule with rhizoidal filaments that ramify between host cells, forming numerous secondary pit connections with host cells. All reproductive structures develop from outer cortical cells. Tetrasporocytes, situated on stalk cells, undergo simultaneous, tetrahedral cleavage to form tetraspores. Spermatia are formed continuously by oblique cleavages of the elongate spermatial generating cells. This results in spermatial clusters consisting of 4–8 spermatia in an alternate arrangement. Carposporophyte development is procarpial. The carpogonium is part of a six-celled branch including a sterile cell that is formed by the basal cell. The carpogonial branch is attached laterally to an obovate supporting cell that also forms an auxiliary cell, presumably formed prior to fertilization. After fertilization the carpogonium temporarily fuses with the auxiliary cell apparently to transfer the diploid nucleus and initiate further fusion with the subtending supporting cell to form an incipient fusion cell. The auxiliary cell portion of this fusion cell divides to form gonimoblast initials that continue to divide, forming gonimoblast filaments whose terminal cells differentiate into carpospores. The remainder of the fusion cell enlarges by continual fusion with adjacent vegetative cells. The resultant carposporophyte consists of a basal, multinucleate fusion cell supporting a hemispherical cluster of gonimoblast filaments with terminally borne carpospores. Vegetatively, Leachiella resembles several other parasitic red algae but it is clearly separated by the procarp, carposporophyte development and structure, and tetrasporocyte cleavage.     

THE FINE STRUCTURE AND SCALE FORMATION OF CHRYSOLEPIDOMONAS DENDROLEPIDOTA GEN. ET. SP. NOV.(CHRYSOLEPIDOMONADACEAE FAM. NOV., CHRYSOPHYCEAE)1

Chrysolepidomonas gen. nov. is described for single-celled monads with two flagella, a single chloroplast, and distinctive canistrate and dendritic scales. The type species, Chrysolepidomonas dendrolepidota sp. nov., is described for the first time. The canistrate scales bear eight “bumps” on the top surface, and the dendriticscales have a tapered base with a quatrifid tip. These organic scales are formed in the Golgi apparatus and storred in a scale reservoir. The scale reservoir is bounded on two sides by the R₁ and R₂ in microtubular roots of the basal apparatus. The cyst (=stomatocyst, statospore) forms endogenously by means of a silica deposition vesicle. The outer cyst surface is smooth, and the pore region is unornamented. Two other organisms bearing canistrate and dendritic scales, previously assigned to the genus Sphaleromants, are transferred to the genus Chrysolepidomonas. They are C.angalica sp. nov. and C. marine(Pienaar) comb. nov. The distinguishing features of Chrysolepidomonas and Sphaleromantis are discussed. A new family, Chrysolepidomonadceae fam. noc., is described for flagellates covered with organic scales.     

PHYSOSTOMA CALCARATUM SP. NOV., A TENTACLED SEED FROM THE MIDDLE PENNSYLVANIAN OF KANSAS

A new species of Physostoma is described from Kansas coal balls of Middle Pennsylvanian age. The seed is small, ovoid, and radially symmetrical. The integument consists of 6–10 rounded segments, fused in the lower half of the seed but free in the upper. Distinct spurs are formed by the segments near the base of the seed. The integument is essentially non-sclerified and has a distinct blow-off epidermis. Each segment is supplied by a single vascular trace. The pollen reception mechanism consists of a short cylindrical salpinx, a bell-shaped lagenostome, and a shallow plinth. A central column is present within the salpinx. It is suggested that the Upper Carboniferous seed genera Conostoma and Physostoma may have been derived from the Lower Carboniferous genera Salpingostoma-Euryostoma and Genomosperma-Hydrasperma, respectively.     

AUREALCAULIS CROSSII GEN. ET SP. NOV., AN ARBORESCENT,OSMUNDACEOUS TRUNK FROM THE FORT UNION FORMATION (PALEOCENE), WYOMING

Aurealcaulis crossii gen. et sp. nov., is based on permineralized trunks of an osmundaceous tree fern from the Paleocene Fort Union Formation from near Bitter Creek Station of southwestern Wyoming. This new species is characterized by centripetal (exarch) development of its xylem strands which form part of the leaf traces. Most of the leaf traces depart the stele as two segments that fuse into a single C-shaped petiole vascular strand outside of the outer cortex. Stipular expansions of the petiole bases of this species lack sclerenchyma, and roots arise from the lateral edges of leaf traces in the inner cortex. The family Osmundaceae and subfamily Osmundoideae are slightly emended to accept genera assignable to this family and subfamily with exarch protoxylem in their steles. Foliage similar to Osmunda greenlandica (Heer) Brown, which is possibly the leaf form of A. crossii, occurred next to an axis of this species which was in growth position. This axis was anchored in a lignite suggesting that this species grew under swampy conditions. Aurealcaulis crossii is the first arborescent member of the Osmundaceae of Tertiary age and the second arborescent form in this family reported from the Northern Hemisphere.     

OCTOSPORIELLA COLORADOENSIS GEN. ET SP. NOV., A NEW TETRASPORALEAN GREEN ALGA FROM TWO COLORADO MOUNTAIN LAKES1

A new green alga, Octosporiella coloradoensis, belonging to the order Tetrasporales, family Tetrasporaceae, is described from Colorado mountain lakes. Colonies are planktonic or attached, the latter often forming loosely aggregated colonial complexes, thus creating an irregularly shaped complex. Individual colonies are spherical and consist of eight subcolonies, with each subcolony having spherically arranged octads of cells. Each vegetative cell bears two pseudoflagella that extend well beyond the colonial sheaths. Cell division is by eleutheroschisis and may be synchronous or asynchronous. Daughter colony formation is apparently coenobic, with each cell in the octad forming new subcolonies of eight cells each. Zoospore formation may precede daughter colony formation but the flagella remain rigid and non-motile. Large akinetes form in response to nutrient depletion. These germinate to produce eight aplanospores which divide to reconstitute a typical colony of Octosporiella. Sexual reproduction was not observed.     

新疆一新蜥脚类

本文记述了新疆中侏罗世蜥脚类恐龙的克拉美丽龙新亚科的一新属种——戈壁克拉美丽龙,并对新亚科的建立及其所属地质时代进行了分析讨论。     

云南西双版纳热带雨林区钩马陆科一新属新种（倍足纲：异蛩目）

本文记述一新属,菌肢马陆属Ａｇａｒｉｃｏｇｏｎｏｐｕｓ ｇｅｎ．ｎｏｖ．,隶属于异蛩目,钩马陆科。雄体的生殖肢之后面伸出一对相当大的菌状突起而有别于其他各属,并且生殖基节顶端具有３对裂叶相互把握为三叶菌肢马陆Ａ．ａｃｒｏｔｒｉｆｏｌｉｏｌａｔｕｓ ｓｐ．ｎｏｖ．之基本特征。这一新类群生活在我国云南热带雨林区。     

THALASSOCHYTRIUM GRACILARIOPSIDIS (CHYTRIDIOMYCOTA), GEN. ET SP. NOV., ENDOSYMBIOTIC IN GRACILARIOPSIS SP. (RHODOPHYCEAE)

Thalassochytrium gracilariopsidis gen. et sp. nov. is an endosymbiotic, polycentric, zoosporic fungus that infected cultures of the red alga Gracilariopsis sp. Based on the posteriorly uniflagellate zoospore and the platelike cristae of the mitochondria, the fungus is placed in the Chytridiomycota. Ultrastructurally, the fungal zoospore is distinguished by the anterior position of the kinetosome, a unique microbody-lipid globule complex, an electron-opaque helix associated with the kinetosome and lipid globules, and a beaked nucleus. Zoospores are positively phototactic, and the unusual helix might constitute part of the photosensory apparatus. Zoospores lack certain taxonomically important structures, such as a rumposome, props, a nonflagellated kinetosome, and flagellar roots. The organism does not fit into any described genus, and the features of its zoospore differ from those of any described order. The fungal thallus is polycentric with multinucleate, septate hyphae. Haustoria form within the algal cells. The fungus does not appear to cause major harm to its host and seems to be host specific. However, during intense sporulation of the fungus, degradation of host chloroplasts was observed in medullary cells.     

NEW ENDOLITHIC CYANOPHYTES FROM THE NORTH ATLANTIC OCEAN: I. CYANOSACCUS PIRIFORMIS GEN. ET SP. NOV.1

This paper describes a new genus and species of endolithic microorganism, Cyanosaccus piriformis Lukas and Golubic (Cyanophyta, Pleurocapsales). It is characterized by 1) having one to four spherical to pear-shaped cells within a stalked, gelatinous sheath, 2) its mode of reproduction by release of a large number of baeocytes produced by the proximal daughter cell following transverse binary fission of the parent cell, and 3) its ability to bore into and dwell within carbonate substrates in the marine environment. Its habit of asymmetrical sheath production allies it with the common microboring genera Hyella and Solentia within the family Hyellaceae. Cyanosaccus is a common inhabitant of mollusk shells found in water depths ranging from +0.5 to –75 m MLW on the eastern Florida continental margin and in carbonate sands or rocks in the intertidal and subtidal zones of the Bermuda and Bahama Islands. Its distribution within and among inhabited substrates is patchy due to its mode of reproduction and growth.     

四川自贡大山铺蜀龙动物群——简报Ⅲ.蜥脚类

本文记述了中侏罗世蜥脚类一新属种——巴山酋龙(Datousaurus bashanensts gen. et sp. nov.)对李氏蜀龙(Shunosaurus lii)的特征进行了补充,讨论了它们在蜥脚类进化过程中的位置。     

MORPHOLOGY OF THE SUBANTARCTIC RED ALGA CENACRUM SUBSUTUM GEN. ET SP. NOV. (RHODYMENIALES) FROM MACQUARIE ISLAND1

The red alga Cenacrum subsutum gen. et sp. nov. is described from material collected at Macquarie Island in the subantarctic between November 1977 and February 1978. The habit and carposporophyte development are similar to members of the family Rhodymeniaceae (Rhodymeniales), but certain vegetative features are unique. The frond is a variously incised or lobed foliose blade with hollow apices above and a medulla which becomes progressively filled basipetally with ingrowing rhizoidal filaments. Details of carpogonial branch, auxiliary cell, connecting cell and gonimoblast anatomy are given, as well as observations on the habitats and distribution of the species.