PISCES. 83 



sent tellement semblables au P. gigas du Portlandien qu il est 

 presque impossible de les distinguer." 

 Localities. Upware, Brickhill, Potton. 



S. Europe. St Croix, Landeron, Neuchatel, Thoiry, Alle- 

 moque (dept. de TAin). Urgonien and Neo- 

 comian (de Loriol and Gillieron). 



Otodus, sp. 



A short and stout hastate tooth. The root is massive but not 

 expanded ; two slight enamelled eminences on its sides represent 

 the lateral denticles of the genus. 



Length. 1 inch. 



Some deeply biconcave sharks' vertebrae, measuring 1 — 3 inches 

 in diameter, are likely to belong to the same species. 



Localities. Upware, Brickhill, Potton. 



Besides these well-marked types, several other species of fishes 

 occur at Upware and Brickhill, and have been enumerated amongst 

 the 'derived' fossils, though some of them may be proper to the 

 bed. There is a particularly fine dorsal spine of Asteracanthus 

 ornatissimus from Upware in the Woodwardian Museum, measuring 

 7 inches in length ; and the jaws of Ischyodus Townshendi are 

 found in fine condition both at Upware and Potton. Other species 

 of Chimeroid jaws also occur. 



