ICHTHYOSAURUS. 31 



of the series referred to Ophthalmosaurus icenicus (p. 10). 

 One of the teeth shows the thick investing coat of cement 

 on the root ; but the other, which is in germ, exhibits the 

 inner fluted layer. The teeth agree precisely with the 

 type tooth of I. hildesiensis, figured by Koken in the 

 ' Zeitschr. deutsch. geol. Ges.' vol. xxxv. pi. xxiv. ng. 3 ; 

 and the vertebral centra apparently closely resemble the 

 lateral view of a dorsal centrum given in fig. 2 of the 

 same plate. Presented by H. F. Mills, Esq,, 1874. 



39158. The centra of an associated anterior cervical, middle (a) 

 and early posterior (b) dorsal vertebra, apparently belonging 

 to the same species as the preceding ; from the Kimeridge 

 Clay of Kimeridge, Dorsetshire. In the cervical the 

 vertical diameter is 0,062 and the transverse 0,071 ; in 

 the middle dorsal these dimensions are 0,079 and 0,087: 

 and in the posterior dorsal 0,065 and 0,064. The middle 

 dorsal appears indistinguishable from the vertebrae of the 

 preceding series. The cervical is somewhat wider than 

 that of I. hildesiensis, figured by Koken, op. cit. fig. 1. 



Bowerbanlc Collection. Purchased, 1865. 



Ichthyosaurus leptospondylus, Wagner l . 



Imperfectly known, but closely allied to if not identical with the 

 following. Wagner first figured two teeth in the Abh. k. bay. 

 Ak. Wiss. vol. vii. pt. 1, pi. vi. figs. 14-19 (1853), and subsequently 

 several portions of an imperfect skeleton in vol. ix. pt. 1, pi. vi. 

 (1861). The latter specimens comprise teeth, part of the sclerotic 

 of the eye, scapulae and coracoids, a vertebral centrum, and the 

 disconnected bones of a paddle. This species was referred to the 

 present group by Kiprijanoff in the ' Mem. Ac. Imp. St. Petersbourg/ 

 vol. xxviii. art. 8, p. 91. 



Hah. Europe (Bavaria). 



42833. Part of a slab of limestone, showing the frontal aspect of 

 (Fig.) the rostral portion of the cranium ; from the Kimeridgian 

 Lithographic limestones of Eichstadt, Bavaria. Eigured 

 by Meyer in the 'Palaeontographica,' vol. xi. pi. xxxiii., and 

 provisionally referred to the present species. The resem- 

 blance of the teeth to those of the type specimens figured 

 by Wagner, op. cit., leaves little doubt as to their specific 

 identity. The form of the rostrum and the structure 

 of the teeth closely resemble the corresponding parts in 

 I. entheciodon. Van Breda Collection. Purchased, 1871. 

 1 Gelehrte Anzeigen, vol. xxxvi. p. 20 (1853). 



