No. 534] NOTES AND LITERATURE 



it. but that the animals now included in that group represent a 

 class distinct from all other vertebrates T, for one. will not for a 



The fundamental error made by Dr. Jaekel, as the reviewer 

 sees it, is the attempt to base a classification of vertebrates on a 

 single character. This has always failed in the the past and 

 must, in the nature of the case, fail in the future: since classifica- 

 tion, if it is to mean anything, must take into consideration the 

 entire organization. The paper is full of many other smaller 

 errors, errors of knowledge and errors of judgment. One of 

 these errors is relating such widely distinct forms as Cerater- 

 peton and Diplocaulus. 



The same author has^ given a study of the limbs of the oldest 



paper is little more than a republication of parts of the essays 

 of other investigators. 



Dr. Williston (17) has recently published another essay on 

 the Permian fauna of Texas in which he gives especially a study 

 of the vertebras and adopts the view of Cope as to the ultimate 

 fate of the elements of the rhachitomous vertebra. He regards 

 Eomu rants copci Will. (Eosauravus punctulatus (Cope)) as 

 allied to Hylonomus and for that reason "the oldest known 



