SYSTEMATIC REVISION OF THE SUBORDER. 59 



Revised description : 



(i) L,arge diastemal notch with few degenerate teeth or none. (?) 



(2) Maxillai^- canine and incisor teeth greatly enlarged. (?) 



(3) Teeth with crenate cutting edges. (?) 



(4) Neural arch early coossified with centrum. 



(5) Change in length of bottom line of vertebrae not marked. 



(6) Anterior dorsals without keel or wide intercentral face. A process on 



lateral edge of centrum marking position of capitulum of rib. 



(7) Spines sharply recurved in posterior lumbar region so that the last long 



spine overhangs the abruptly shortened spines of the sacrals and 



caudals. 

 (9) L,imb bones with well-marked articular faces. 

 (10) Humerus with well-developed entepicondyle and ectepicondylar process, 

 (i i) Abdominal scutes present. 



(12) Tail relatively short. 



(13) Size, varying in diflferent species. From 2 to 2.6 meters long. 



Naosaurus claviger Cope. 



Am. Nat., vol. xx, 1886, p. 544. 



Trans. Am. Phil. Soc, vol. xvi, 1888, pp. 287 and 293, plates 2 and 3. 



Type: The type is doubtful as shown below. The original description was 

 made from a skull and vertebrae which are not connected to-day by reference or 

 number. I shall accept the series of vertebrse as the type specimen, as it is undoubt- 

 edly the series described by Cope, and the skull is now connected with it only by 

 inference. 



1. A series of twenty-six vertebrse comprising a nearly complete vertebral 

 column to the first caudal, but not preserved in natural order and the spines imper- 

 fect; the pelvis and several ribs. No. 4002 Am. Mus. Nat. Hist., Cope, coll.; from 

 Cofifee creek, a tributary of the Big Wichita river, in Vernon county, Texas. 



2. The left half of a skull lacking the anterior end of the muzzle. (This skull 

 very possibly belongs with No. 4002.) No. 4036 Am. Mus. Nat. Hist., Cope, coll.; 

 from Texas. 



Original description: This was furnished by a comparative table. See the 

 description of Naosaurus cruciger. 



In 1888 Cope repeated this description of the genus in an account of 

 N. claviger. He altered his analysis of the species of the genus somewhat, 

 as follows : 



I. Neural spines distally cylindric : 



Distal transverse processes represented by tuberosities A', cruciger. 



II. Neural spines distally dilated and compressed : 



Palatine teeth small, widely spaced N. claviger. 



Palatine teeth large, closely packed M. microdus. 



Revised description : See Naosaurus cruciger below. 



As shown in the morphological description, the clavate distal end of 

 the spines is not a specific character, but a character of the cervical vertebrae 

 in all species. 



