﻿68 CHTMJEROTDEI. 



1870. Ischyodus brevirostris, E. T. Newton, Quart. Journ. Geol. Soc. 



vol. xxxii. p. 326, pi. xxi. fig. o. [Teeth; British Museum.] 

 1878. Ischyodus brevirostris, E. T. Newton, Chinneroid Fishes Brit. 



Cret. Rocks (Mem. Geol. Surv.), p. 27, pi. ix. 

 1888. Ischyodus brevirostris, J. W. Davis, Trans. Roy. Dublin Soc. [2] 



vol. iv. p. 42, pi. vii. figs. 10-13. 



Type. Imperfect palatine tooth. 



Mandibular tooth notably robust, with a deeply sinuous oral 

 margin, acute eminences corresponding to the outer tritors, and 

 the beak prominent ; post-oral margin much less vertically inclined 

 than the symphysial margin ; beak-tritor minute ; outer tritors well- 

 developed ; median tritor narrow or of moderate width, occupying 

 the greater portion of the oral surface immediately behind the 

 anterior outer tritor. Palatine tooth with the posterior inner tritor 

 of moderate or large size, and the median tritor not extending so 

 far forwards as this ; outer tritor much elongated. Vomerine tooth 

 much deeper at the symphysis than externally. 



Form. 6f Loc. Lower Greensand : Kent. Albian : Kent, England, 

 and St.-Croix, Switzerland. Cenomanian and Turonian : Cambridge- 

 shire and Kent. Greensand : Amuri Bluff, New Zealand {Newton 

 and Davis). 



(i.) Lower Greensand, Maidstone. 



41682 a. Elongated right mandibular tooth, described and figured 

 by E. T. Newton, op. cit. p. 31, pi. ix. fig. 10. 



Toulmin-Smith Coll. 



P. 1155. Fragmentary left mandibular tooth, noticed by E. T. New- 

 ton, op. cit. p. 28. Egerton Coll. 



P. 3091-2. Two imperfect mandibular teeth. Ennishillen Coll. 



P. 475. Right palatine tooth, assigned to " Chimcsra (Ischyodon) 

 agassizii " by Agassiz, torn. cit. pi. xl. c. figs. 14, 15. 



Egerton Coll. 



(ii.) Gault, Folkestone. 



47173 a, 47177. Right mandibular tooth and a pair, the former 

 and one of the latter being figured by E. T. Newton, 

 op. cit. pi. ix. figs. 3-5. Gardner Coll. 



47175, 47178, P. 27, P. 28. Four pairs of mandibular teeth. 



Gardner Coll. 



47173-74, P. 29. Six mandibular ^teeth, three of each side. 



Gardner Coll. 



