204 



SCIENCJE. 



[Vol. I., No. 7. 



VERTEBRATES. 

 Discovery of the blood-circulation. — From a 

 careful study of the works of Colombo, and a com- 

 parison of dates, ToUin concludes that Colombo was 

 not an original discoverer of the pulmonary circula- 

 tion, but merely appropriated the wbrk of Servetus. 

 — {Arch. path. anat. phys., xci. 18S3, 39.) H. N. M. 



[459 

 Internal polarization of nerves. — As the result 

 of experiments carried on in Loven's laboratory, 

 Tigerstedt concludes, that, when the polarizing cur- 

 rent is opened, the polarization instantaneously 

 reaches its higliest value, and then continuously 

 decreases. The decrease is at first rapid, then falls 

 more and more slowly; so that polarization still re- 

 mains long after the opening of the polarizing current, 

 and only asymptotically approaches the zero point. — 

 (Mitth. physiol. lab. Carol inst. Stockh., i., ii., 1882.) 

 H. N. M. [460 



Action of the intercostal muscles in breath- 

 ing. — Lukjanow has made fresh observations on this 

 long-disputed subject. In his experiments, rabbits 

 and dogs were used; the breathing of the former 

 being mainly diaphragmatic, that of the latter chiefly 

 costal. On examination of the intercostal spaces, 

 exposed by removing the skin and the pectoral mus- 

 cles, he found that the changes in their width dui'ing 

 inspiration depended on the thoracic region observed. 

 The upper two or three intercostal spaces were nar- 

 rowed in inspiration ; the lower three or four, widened ; 

 the intermediate remained unchanged. The phe- 

 nomena were the same in forced and in quiet breath- 

 ing, and essentially alike in rabbit and dog, though 

 more conspicuous in the latter animal. Moreover, 

 during artificial respiration, the same changes in the 

 widths of the various intercostal spaces were observed 

 as in normal breathing. The author concludes, that 

 it is most probable that the view of Henke and Briiche 

 is correct, in accordance with which the intercostal 

 muscles have no proper duties as muscles, but sim- 

 ply form an elastic membrane, enclosing the thorax. 

 Very considerable difficulties oppose the acceptance 

 of this view, and these Lukjanow to some extent 

 recognizes. He concludes by stating that the full 

 explanation of the phenomena observed by him can- 

 not be given until all the respiratory movements of 

 the ribs have been separately investigated. — [Pfliig. 

 arch., XXX. 1883, 82.) h. n. m. "[461 



Tarsus of birds and dinosaurs. — This paper 

 by Georg Baur forms an important contribution to 

 our knowledge of the resemblances of the tarsus of 

 birds to that of dinosaurs, especially Compsognathus. 

 The tarsus of birds as shown by embryos is composed 

 of a tibiale, fibulare, and a piece rejiresenting tarsals 

 1-.5; the latter anchylose with met. 2-4, and the two 

 first with the tibia. Contrary to the observations of 

 Prof. E. S. Morse, the ascending process is held to be 

 a rather late product, but an "integral part, of the 

 tibiale. By an extended study of the tarsus among 

 the dinosaurs, he finds the following points of resem- 

 blance to birds: 1°. That the tibia and fibula be- 

 come slim in embryo birds in the same way as in the 

 evolution of dinosaurs. 2°. The similar blending of 

 fibulare and tibiale, and the position of the fibulare 

 imder the tibia. 3°. The blending of the first row 

 with the tibia in both cases. 4°. The morphological 

 relations of the ascending process: this is small or 

 absent in early dinosaurs, and is slowly evolved. .5°. 

 The resemblance of the development of the meta- 

 tarsals in birds to the evolution of the same parts in 

 dinosaurs. 6°. The similar decrease in the number of 

 the toes. — {Morph. jahrb., 1882, 417.) J. a. j. [462 



Permian fishes and reptiles from Texas. — 



Professor E. D. Cope exhibited some specimens of 

 fishes and reptiles from the Permian formation of 

 Texas. One of these was a new species of Crossop- 

 terygian fish, which he named Eotosteorhachis cicero- 

 nius. It exhibited some important characters of the 

 posterior cranial region. The base of the skull con- 

 sists of ossified parachordals ; and these embrace the 

 chorda dorsalis posteriorly, and are continued for a 

 short distance posteriorly as a tube. Anteriorly the 

 chordal groove is open. He considered the cranial 

 structure to be an excellent illustration of a perma- 

 nent embryonic type. 



The most interesting reptile was a new genus 

 which occupies a place between the Pelycosauria with 

 molar teeth and those with raptorial teeth, but with 

 more resemblance to the former, or Diadectidae. The 

 teeth are placed transversely in the jaws, but the 

 crowns terminate in an incurved apex, without ledge. 

 He named the genus Chilonyx, and referred it provis- 

 ionally to the Bolosauridae. The typical species is 

 the Bolosaurus rapidens, — ^an animal with a skull as 

 large as that of a terrapin, and with robust limbs. 

 The surface of the skull is divided by grooves into 

 numerous swollen areas; and some of these on the 

 lateral occipital region are developed to tuberosities, 

 like the rudimental horns of Phrynosoma lioug- 

 lassi. — {Acad. nat. sc. Philad.; meeting March 6.) 



[463 



Dinodipsas, a ne-w venomous snake. — Profes- 

 sor E. D. Cope drew attention to a recent important 

 discovery, made by Prof. Peters of Berlin, of a new 

 genus of venomous snakes, Dinodipsas. The speaker 

 stated that he regarded the genus as pertaining to 

 the Causidae, — a family he had proposed as a sub- 

 family in his first paper read before the Academy in 

 1859. As Causus, the only genus heretofore known, 

 is African, the statement of Peters, that Dinodipsas 

 is South American, adds an important fact to geo- 

 graphical zoology. Prof. Cope then corrected a state- 

 ment made by Peters in his herpetology of the Reise 

 nach Mozambique, that he (Prof. Cope) had referred 

 Causus to the vipers. In 1859 he had divided the 

 venomous snakes with vertical and hinged maxillary 

 bones into the subdivisions of the rattlesnakes, the 

 vipers, the Atractaspines, and the Causiues. He then 

 designated the entire group Viperidae, after Bona- 

 parte, and had not until later used Dumeril and Bib- 

 ron's terminology. This did not, however, justify 

 Peters in stating that he has referred the genus Cau- 

 sus to the vipers, and that he (Peters) was the .author 

 of a separate family, the ' Vipernattern,' to receive 

 that genus and Dinodipsas. — {Acad. nat. sc. Philad.; 

 meeting March 5. ) [464 



Mammals. 



On Halichoerus gryphus. — Nehring, basing his 

 remarks upon the result of an examination of a full- 

 grown male gray seal, captured at Goehren, island 

 Riigen, gives some valuable information in regard to 

 the species. The intestines of the Goehren specimen, 

 which measured 38 metres, i.e., 17 times the length 

 of the animal, were filled with partially digested fish- 

 vertebrae, and immense numbers of the nematoid 

 worm, Ascaris osculata. A comparison of skulls in 

 the museums of the universities of Greifswald and 

 Berlin shows that great variation exists; making it 

 probable that the three species of Halichoerus recog- 

 nized by many zoologists represent but the variations 

 of a single one. The presence of six molars, either 

 on one or both sides of the upper jaw, in 8 out of 34 

 skulls examined, is noted, and is regarded as repre- 

 senting a tendency to reversion rather than an abnor- 



