§34. 



FOSSIL FISHES OF THE CHALK. 



343 



many other forms have been discovered in secondary and 

 tertiary strata ; thus affording evidence that the ancient seas 

 were inhabited by several genera of this curious and now 

 limited group.* 



Ligx. 71. — Maxillary bone of a fish allied to the chimjera; from 

 the chalk near lewes. 



(Endaphodon Mantelli; half the natural size.) 



34. Htpsodon. — Teeth of large fishes, belonging to that 

 division called Sauroid, from their combining in their 

 structure certain characters of reptiles,f have been found in 

 the white chalk, gait, and greensand. They are of a 

 conical form, longitudinally striated externally, and bearing 

 a general resemblance to those of crocodiles, for which they 

 were formerly mistaken. Remains of several other large 

 fishes are preserved in various private collections, but 

 have not yet been scientifically examined. 



There is however a genus of extinct fishes, allied to the 

 Pikes, which has been established by M. Agassiz from 

 some vertebrae and other bones. It is named Hypsodon, 

 from the straight and pointed form of the teeth. A jaw 

 with teeth, some vertebrae, and the os hyoides, of this fish 



* Sir P. G-. Egerton has very recently laid before the Geological 

 Society an admirable memoir on the fossil Chimceroid fishes, 

 f Medals of Creation, vol. ii. p. 650. 



