226 0. P. Hay — Notes on species of Ichthyodectes. 



This species appears to be nearest to Prof. Cope's I. anaides. 

 It differs, however, in having larger teeth, as well as in some 

 other respects. In my possession is the maxilla of a specimen 

 of the last named species which has the depth from the upper 

 surface of the palatine condyle to the tooth-line equal to that 

 of L cruentus. In this maxilla of 1. anaides I find about 10 

 teeth to the inch; in I. cruentus there are only 7 teeth to the 

 inch. The teeth being larger, we find that the alveolar border 

 of the maxillary is thicker than in I. anaides. Indeed, the 

 whole bone is of heavier construction. In I. anaides the 

 mesial surface is nearly flat, or even has a wide shallow groove 

 some distance below its upper border. In I. cruentus the 

 mesial surface is decidedly convex. In I. anaides the upper 

 border is flattened at right angles with the outer surface of the 

 bone ; while in I. cruentus it is gradually rounded off, from a 

 sharp outer edge, into the mesial surface. 



The palatine condyles of the maxillae of the two species are 

 quite different. Figure 2 represents that of I. anaides, of 

 natural size. Figure 3 shows that of 1. cruentus, also of nat- 

 ural size. Further descriptions are not required. 



From I. ctenodon (Cope, Cret. Vert., p. 208, pi. xlvi, figs. 

 1-4) this species differs in having a high, not a low, palatine 

 condyle. The maxillary of I. ctenodon is said to be a rather 

 thin and narrow bone. 



I. hamatus has a maxillary whose dental border is very con- 

 cave. According to Cope's figure, there must have been 10 or 

 12 teeth to the inch (Cope, Cret. Vert., p. 209, pi. xlvi, fig. 5). 



1. prognathic also must have had smaller teeth, judging 

 from Cope's figure of the premaxillary (Cope, Cret. Vert, p. 



