51 



m. Slab showing a rather larger imperfect skeleton ; from Barrow. 



The ventral aspect of the skull is exposed, and portions of the 



paddles are well preserved. 



n. Slab with an imperfect medium-sized skeleton ; from Barrow. 



The skull and paddles are seen from the dorsal aspect. 



o. Slab showing an imperfect medium-sized skeleton; from 



Barrow. 



p. Slab exhibiting a nearly entire adult skeleton ; from Barrow. 



The dorsal aspect of the skull and pectoral paddles is exposed ; 



the latter being well presrved. 



ICHTHYOSA URUS TENUIROSTRIS. 



Conybeare, Trans. Geol Soc, ser. 2, vol. I, p. 108 (1822). 



JFrom the Lower Lias. 



Of the following specimens it is probable that some belong to 

 /. lattfrons, Koning, but the whole series seems to render it very 

 doubtful whether the latter is a valid species. 



a. Slab showing central aspect of an adult skeleton ; from Long 

 Sutton, Somersetshire. The pectoral girdle is beautifully seen. 

 The rostrum has the medium-length characteristic of this species, 

 as distinguished from /. latifrons. 



b. Slab showing a larger imperfect skeleton ; from Barrow-on- 

 Soar, Leicestershire. The ventral aspect of the pectoral girdle is 

 exposed. 



c. Slab showing a smaller imperfect skeleton; from Barrow. 

 The frontal aspect of the skull is exposed and the paddles are well 

 preserved. 



d. Slab showing the right lateral aspect of an adult full-grown 

 skeleton ; from Barrow. The large size of the orbit and slender- 

 ness of the rostrum are characters of /. latifrons. The posterior 

 notch in the coracoid is exhibited. 



e. Slab showing the left lateral aspect of a rather smaller 

 skeleton ; from Barrow. 



