RECENT ADVANCES IN SCIENCE 241 



a bipedal carnivore seems certain. The author suggests that 

 the remarkably small and feeble forelimbs were of assistance 

 in minor changes of position, when prone ; or when rising 

 to a sitting posture ; and also for receiving the weight of the 

 fore part of the body when bringing its full length to the 

 ground. In these conjectures he may be right. But we hesi- 

 tate to adopt his suggestion that it was, in part at any rate, 

 a carrion eater. 



Prof. Herman Douthitt {Contributions from the Walker 

 Museum, vol. ii. No. 14-41, 191 7) describes at length the 

 structure of the curious amphibian known under the name 

 of Diplocaulus. Much already has been written on this theme, 

 but the author has had the advantage of studying far more 

 perfect material than has yet fallen to the lot of any other 

 investigator. As a result, he has been able to set at rest 

 many doubtful points in regard to the morphology of the 

 skull, and has also added materially to our knowledge of the 

 rest of the skeleton. 



Prof. Samuel W. Williston (Contributions from the Walker 

 Museum, vol. ii. No. 4, 191 8) reviews the present state of 

 our knowledge of the evolution of the reptilian vertebra, and 

 in a second contribution to the same number discusses the 

 osteology of some American Permian vertebrates. 



In the first-mentioned paper he confirms the views expounded 

 years ago by Cope on this theme, adding thereto a number 

 of new facts, and some most excellent text figures. In his 

 second paper he adds materially to our knowledge of the oste- 

 ology of the primitive amphibians Eryops and Chenoprosopus, 

 thanks to the discovery of new material. He also brings to 

 light a number of new facts in regard to the very remarkable 

 theromorph reptiles Naosaurus, Edaphosaurus, and Sphena- 

 codon. As he remarks, " no valid characteristics distinguish- 

 ing Edaphosaurus from Naosaurus have yet been found in the 

 skulls, or appendicular skeleton " ; but, he now points out, there 

 is a well-marked difference in the remarkably elongated neural 

 spines of the vertebrae, which make these creatures among the 

 most extraordinary that have ever lived. In Naosaurus these 

 spines have their free ends broadly dilated and thickened, 

 while in Edaphosaurus they are slender and pointed. Finally 

 he describes a new genus and species of the Diplocaulidoe, 

 under the name Platyops parvus, based on two specimens 



