1883.] NATURAL SCIENCES OF PHILADELPHIA. 5*7 



through the chord when studied in transverse sections. The poste- 

 rior columns are projected above the plane of the lateral columns 

 and exhibit distinct diiferences in the arrangement of nerve-fibres. 

 In lacertilians and crocodilians the commissures are perforated 

 longitudinally by a pair of columns of nerve-fibres. In ophidians 

 the posterior nerve-roots are seen to be rudimentary or absent and 

 when present to tend to arise from the cervix cornu of the poste- 

 rior horn of gray matter. In chelonians the motor-cells are few 

 in number; the anterior median fissure is of great width, the com- 

 missure of relatively great size, and the reticular fibres lying to the 

 lateral aspect of the gray columns are unusually well developed. 



February 27. 

 The President, Dr. Leidy, in the chair. 

 Thirty-seven persons present. 

 Walter Rogers Furness was elected a member. 



On DinodijysaK and Causus. — Prof. Cope drew attention to a 

 recent important discovery made by Prof. Peters, of Berlin, of 

 the new genus of venomous snakes, Binodipsas. He stated that 

 he regarded the genus as pertaining to the Gausidse^ a family he 

 had proposed as a subfamily in his first paper read before the 

 Academ\^ in 1859. As the only genus heretofore known, Gausus, 

 is African, the statement of Peters tljat Dmodipsan is South 

 American, adds an important fact to geographical zoology. Prof. 

 Cope then corrected a statement made by Peters in his Herpetology 

 of the Reise nach Mozambique (1882), that he (Prof. Cope) had 

 referred Gausus to the Vipers. In 1859 he had divided the 

 venomous snakes with vertical and hinged maxillary bone, into 

 the subdivisions of the rattlesnakes, the vipers, the Atractos- 

 pidines and the Causines. He then designated the entire group 

 Viperidffi after Bonaparte, and had not until later used Dumeril 

 and Bibron's term Solenoglypha for that division. But this did 

 not justify Peters in stating that he had referred the genus Gausus 

 to the Vipers, and that he, Peters, was the author of the separate 

 family- to receive that genus and Dinodipsas, the " Vipernattern." 



He also corrected some other references to himself by Prof. 

 Peters in the Reise nach Mozambique. In one of these, Peters 

 had supposed him to refer to a combination of the genera Brem- 

 ceps and Ghelydohatrachus b}^ Peters, when he had really separated 

 them. Prof. Cope said that his language referred to their union 

 in the same family by Peters, which he did not approve. 



Prof. Petal's also states that the peculiarities of the tongue in 

 the genus Hemisus, described by Steindachner and Prof. Co[)e, 

 nre due to mutilation. Prof. Cope could not coincide with this 

 view, and regards the structures descril^ed as normal. 



The following were ordered to be printed : — 



