ICHTHY0SAURTDJ3. 105 



R. 1174. One of the bones of the middle of a paddle of a large 

 individual ; from Lyme-Begis. JS r o history. 



Specimens ivhich may perhaps belong to this species. 

 2031*. Fragment of the middle portion of a young cranium not 

 {Fig.) improbably belonging to this species ; from Lyme-Regis. 

 Figured by Hawkins in his 'Memoirs on Ichthyosauri &c.' 

 pi. vi. (ed. 1834). The left orbit and nares are shown. 



Haiuhins Collection. 



2032*. Fragment of the rostrum of a somewhat larger skull; from 



{Fig.) Lyme-Regis. Figured by Hawkins, op. cit. pi. vi. The 



teeth are very imperfectly preserved, but one of them 



seems to show the coronal structure characteristic of the 



present species. Haiulcins Collection. 



Ichthyosaurus trigonodon, Theodori \ 

 Syn. (?) Ichthyosaurus crassimanus, Blake 2 . 



Apparently closely allied to the preceding, but with the crowns 

 of the teeth only slightly compressed, and their summits when 

 adult bearing three vertical carina, of which two extend to the base 

 of the crown but the third stops short. This species is confined to 

 the Upper Lias, and was originally recorded from Banz, in Bavaria. 

 There is at present no reason for separating I. crassimanus, of the 

 Whitby Lias ; the entire anterior border of the radius of the type 

 specimen being probably abnormal. 



J Fab. Europe (Bavaria, Wurtemberg 3 , England, and ? France). 



47153. The posterior portion of the cranial rostrum and a part of a 

 mandibular ramus of a medium-sized individual ; from tho 

 Upper Lias of Kingsthorpe, Yorkshire. The broken roots 

 of numerous teeth are shown, together with the crowns of 

 some immature examples. These teeth are of the general 

 type of those of I. platyodon, having smooth crowns, 

 and deeply fluted roots originally covered with cement, 

 which has now disappeared. The crowns have a sub- 

 circular section, but do not show the carina) on the summit ; 

 in which respect they agree with the immature teeth 

 of the Banz specimen noticed on page 2 of Thcodori's 



1 Gelehrte Anzeigen, vol. xvi. p. 9(X> (184.**). 



2 Tate and Blake, ' The Yorkshire Lias,' p. 253 (1870). 



3 See Quenstedt, ' Die Jura,' p. 220 (1858). 



