REPTILES ABUNDANT. 63 



could raise or depress itself in the water at pleasure by a 

 pneumatic operation upon the air tube pervading its shell. 

 Its tentacula, sent abroad over the summit of the shell, 

 searched the sea for prey. The creature had an ink bag with 

 which it could muddle the water around it, to protect itself 

 from more powerful animals, and strange to say, this has 

 been found so well preserved, that an artist has used it in one 

 instance as a pigment, wherewith to delineate the belemnite 

 itself. 



There are many fishes, some of which (acrodus, psammodus, 

 &c.) are presumed, from remains of their palatal bones, to 

 have been of the gigantic cartilaginous class, (placoidean,) 

 now represented by such as the cestraceon. It has been con- 

 sidered by Professor Owen as worthy of notice, that, the 

 cestraceori being an inhabitant of the Australian seas, we 

 have, in both the botany and ichthyology of this period, an 

 analogy to that Continent. The pycnodontes, (thick toothed,) 

 and lepidoides, (having thick scales,) are other families de- 

 scribed by M. Agassiz as extensively prevalent. 



In the English lias there is a vast abundance of the enalio- 

 sauria which we have seen commence in the foreign Mus- 

 chelkalk, and, in addition to these, specimens of Pterosauria 

 or Winged Saurians, a type of being, the most new, perhaps, 

 of all which the geological record has presented to us. The 

 Pterodactyls, as the animals of this order have been called, 

 were saurians of small size compared with their associates, 

 being not larger than a modern cormorant ; but the marvel 

 in their case consists in bat-Lke wings extended upon the 

 fore- finger, by which the animal was enabled to pursue its 

 way in the air. This order became extinct in the time of the 

 chalk formation. The only existing animal of which it may 

 even remind us is the draco volans or flying lizard, which 

 has a membrane by which to support itself in leaping from 

 tree to tree. 



In the proper oolite, there is added an enaliosaurian (the 

 Pliosaur} in which there is a very close approach made to 

 the crocodilian order, but upon a scale of enormous mag- 

 nitude, the animd having apparently been as large as the ex- 



