98 ICHTHYOPTERrGIA. 



Owen in his ' Liassic Eeptilia ' (Mon. Pal. Soc), pt. iii. p. 1 11 

 (reference erroneously given as pi. iii. of Hawkins), who 

 compares it to the specimen figured by him as I. breviceps 

 (No. E. 1157). The teeth have mostly lost their crowns, 

 but a detached crown in the matrix below the mandible 

 exhibits the carination and compression characteristic of 

 the present species. The characteristic straightness of 

 the alveolar border of the posterior portion of the mandible 

 is also well shown. The sclerotic ossifications are perfect. 

 The right frontal region has been split away from its 

 normal position, and is thrust up above the line of the 

 profile. HaivTcins Collection. 



R. 218. The skull and part of the vertebral column of a medium- 

 sized individual, in a broken and somewhat crushed con- 

 dition ; from Lyme-Regis. The structure of the teeth 

 well shown. Purchased, 1882. 



R, 1157. Slab exhibiting the right lateral aspect of a large skull, 

 (Fig.) provisionally referred to this species ; from Lyme-Regis. 

 Figured by Owen in his ' Liassic Eeptilia,' pt. iii. pi. xxix. 

 figs. 1, 35, as 1". breviceps. The teeth exhibit all the cha- 

 racters of those of the present species, but the cranial 

 rostrum is abnormally short and the number of teeth 

 reduced. It is doubtful if the shortness of the rostrum 

 can be considered a specific character, since other speci- 

 mens show considerable variation in this respect. 



Purchased. 



R. 1159. Slab showing the frontal aspect of the skull of a medium- 

 sized individual, together with the anterior portion of the 

 vertebral column ; from Lyme-Regis. The skull is crushed 

 flat, but the characteristic contour of the supratemporal 

 fossae is well preserved. No history. 



R. 1160. Fragment of the upper and lower jaws of a very large in- 

 dividual ; from Lyme-Eegis. One side has been cut and 

 polished, in order to show longitudinal sections of the 

 teeth. No history. 



41220. Fragment of the premaxillae of a medium-sized individual ; 

 from Lyme-Eegis. Several teeth are preserved, and 

 exhibit very distinctly the mode of implantation in the 

 alveolar groove Purchased, 1808. 



