安徽潜山古新世裂齿目一新属兼论中国古新世裂齿类

记述了安徽潜山盆地古新世裂齿目一新属种 ,命名为潜水本爱兽 (Benaiusqianshuiensisgen .etsp .nov .)。标本产于望虎墩组下段底部 ,为一带犬齿和完整颊齿列的左下颌骨。新种的主要特点是 :个体较小 ,下齿列齿式 2 + ?·1·4·3,i2略有增大 ,p1存在但退化成单根且侧扁 ,p3无下后尖 ,p4次臼齿化且无下内尖 ,下三角座前后压缩且下前尖退化 ,m3三叶。中国曾经记述的和被认为是裂齿类的古新世哺乳动物共有 9个属种 :Lofochaiusbrachyo dus、Meiostylodonzaoshiensis、Anchilestesimpolitus、Dysnoetodonminuta、Interogaledatangensis、Pletho rodonchienshanensis、Huananiusyoungi、Yuesthonyxtingae和Simplodonqianshanensis。经过仔细比较研究它们的齿列 ,作者认为 ,Lofochaius、Meiostylodon、Interogale、Plethorodon和Simplodon可能属于裂齿类 ,而Anchilestes、Dysnoetodon、Huananius和Yuesthonyx则可能与裂齿类没有很近的亲缘关系。广东南雄盆地上湖组Lofochaiusbrachyodus的P1和P2退化、P4有一定程度的臼齿化、外架窄、主尖锥状、前尖棱和后尖棱的颊侧端内收 ,显示了裂齿类的特点。湖南茶陵盆地枣市组Meiostylodonzaoshiensis的i2增大、上臼齿主尖锥状、柱尖和后附尖发育、前尖棱和后尖棱的颊侧?     

THE LEPIDOPHYTIC AFFINITIES OF THE GENUS CHINLEA AND OSMUNDITES WALKERI

Chinlea campii Daugherty and Osmundites walkeri Daugherty are species of petrified stems from the Upper Triassic Chinle Formation of Arizona that were described as members of the fern family Osmundaceae. Investigation of additional material indicates that the two species are conspecific and belong to the Lepidophyta. The stems are radially symmetric and have an ectophloic siphonostele in which the xylem cylinder is thick and deeply furrowed. Internal pressure against the xylem cylinder caused by the lateral expansion of the pith in some stems produces what appears in transverse section to be a ring of up to 60 separate xylem strands. Leaf traces are small, terete, collateral and have exarch xylem. They are arranged in a tight spiral. Adventitious roots, secondary xylem, and secondary cortex are lacking. The stems are classified under the binomial Chinlea campii, and other axes that have similar cortical anatomy but in which all vascular tissues have decayed are treated as Chinlea sp. Both types of stems are interpreted as ephemeral aerial shoots of an herbaceous plant. Of the known fossil Lepidophyta, Chinlea is most similar to Pleuromeia and Nathorstiana, but it differs from each of these genera in a number of respects and is therefore included in Lepidophyta incertae sedis.     

THE ANATOMY OF MENASPIS ARMATA AND THE PHYLETIC AFFINITIES OF THE MENASPID BRADYODONTS

The two best preserved specimens of the Upper Permian fish Menaspis armata have been reinvestigated, resulting in new interpretations of a variety of anatomical features. The conclusion is reached that the menaspids cannot possibly be closely related to the chimaeriforms (myriacanthids, squalorajids, and chimaerids), nor to any of those better known bradyodonts (chondrenchelyids, helodontids or edestids) with which they were previously classified. Among the bradyodonts, their closest relatives are probably to be found within the cochliodontids. As far as other elasmobranchiomorphs are concerned, the menaspids may be somehow related to, though surely not direct descendants of, the rhenanids, and it is conceivable that both these groups are derived from the same ancestral forms among the early arthrodires or the arthrodire predecessors.     

中国-日本蕨类植物区系的地理亲缘

本文较详细地分析比较了中国和日本蕨类植物区系的种类组成。两国有7个共同的特有属,有461种共有种。说明两国蕨类植物区系是在两陆块未分离之前共同起源的,此后才有了分化。日本蕨类区系与中国华东地区尤为相近,而与中国西南部即中国-喜马拉雅区系本质上是一致的,但已有较大的不同。     

ORDINAL AFFINITIES OF THE AEGIALORNITHIDAE

The Aegialornithidae of the Eocene-Oligocene, previously regarded as swifts, have been transferred by Brodkorb (1971) to the nightjar order Caprimulgiformes. The fossil forelimb bones representing this early family have now been compared with those of recent species of the true swifts and tree swifts (Apodi in Apodiformes) and with nightjars, Oilbirds and frogmouths (Caprimulgiformes). The corresponding bones in swifts differ consistently from those of nightjars in the greater development of various prominences for muscle attachment. In all critical characters the fossil bones resemble those of swifts, and it is concluded that the Aegialornithidae should be reinstated as a family of the Apodiformes.     

ANATOMY AND AFFINITIES OF PENTHORUM

The genus Penthorum L. consists of two species of perennial herbs, P. sedoides of eastern North America and P. chinense of eastern Asia. Penthorum has long been considered intermediate between Crassulaceae and Saxifragaceae. An anatomical study of both species was undertaken to contribute to a better understanding of the relationships of these plants. Prominent anatomical features of Penthorum include: an aerenchymatous cortex and closely-spaced collateral vascular bundles of stems; one-trace unilacunar nodes; brochidodromous venation, rosoid teeth bearing hydathodes, and anomocytic stomata of leaves; angular vessel elements with many-barred scalariform perforation plates and alternate to scattered intervascular pits; thin-walled non-septate fiber-tracheids; abundant homocellular erect uniseriate and biseriate rays; and absence of axial xylem parenchyma. In general, Penthorum possesses neither the morphological nor the anatomical synapomorphies which define Crassulaceae, and features shared with Saxifragaceae are largely symplesiomorphous. Thus Penthorum is probably best classified in the monogeneric Penthoraceae.     

TONGUE MORPHOLOGY AND AFFINITIES OF THE HAWAIIAN HONEYCREEPER MELAMPROSOPS PHAEOSOMA

Melamprosops phaeosoma has a thick straight tongue with an anterior spoon-like trough, but without any indication of a tube. Its hyoid skeleton has an elongated, flattened basihyale, stout parallel paraglossalia and a concavity along the dorsal surface of the ceratobranchiale. All the tongue muscles could be dissected but the superficial M. mylohyoideus and M. serpihyoideus were too damaged to figure and describe. The M. ceratoglossus and the M. hypoglossus obliquus are large; the latter muscle inserts mainly on the basihyale and ceratobranchiale, but a small number of fibres pass beneath the basihylale. The M. hypoglossus anterior is absent. The morphology of the tongue apparatus of Melamprosops is very similar to that of Ciridops and of Loxops and supports placement of Melamprosops in the Drepanididae. Further it suggests that Melamprosops evolved from an ancestor with a tubular tongue, supporting the suggestion that it evolved from Loxops.