O. P. Hay — Notes on species of Ichthyodectes. 227 



210, pi. xlvi, iig. 6). Cope also states that the palatine condyle 

 of I. prognathic reached " a point above the middle of the 

 alveolar margin of the premaxillary." This is certainly not 

 true of /. cruentus. 



In I. multidentatus (Cope, Cret. Vert., p. 212) the teeth are 

 small, about 12 to the inch, and are marked by ridges and 

 grooves. 



In I. goodeanus (Cope, Proc. Amer. Philos. Soc, xvii, p. 

 176) the maxillary tooth- line is directed upward and inward in 

 front and then becomes convex. The palatine condyle is said 

 to be not protuberant. I. acanthicus (Cope, loc. cit., p. 177) is 

 a small species which has the dentary teeth attenuated and 

 curved inward at the apex. 



Newton has given descriptions of two English species of this 

 genus, I. minor (Egerton) and I. elegans Newt. (Quart. Jour. 

 Geol. Soc, xxxiii, p. 520.) L minor has a very straight man- 

 dibular tooth-line ; L elegans has extremely long, forwardly 

 projecting mandibular teeth. 



Length of portion of maxilla of 1. cruentus here described, 

 100 mm ; depth at middle of palatine condyle, 34 mm ; depth at 

 point 34 mm behind the palatine condyle, 28 mm . 



4x1 



Where the bone is fractured near its distal end there are 

 shown in its interior large medullary cavities, now occupied 

 by calcite. 



The dentary bone which I regard as belonging to this species 

 is showm by figure 4. Nearly the whole of the tooth-line is 

 present, perhaps not more than 3 or 4 teeth being missing. 

 This indicates that there were 30 teeth. The alveolar border 

 is sinuous, being strongly concave behind the middle and rising 

 further behind. In front of the concavity the border is con- 

 vex, and then descends to the symphysis. The convexity 

 appears to correspond to the concavity of the alveolar border 

 of the maxilla ; while the symphysial descent corresponds to 

 the downward slope of the anterior end of the maxilla, which 



