140 AN ATTEMPT TO DESCRIBE THE ANIMALS THAT MADE 



or confound different species together. But to such mistakes he 

 who describes living, or other fossil animals, is alwajs liable ; and it 

 cannot be an unpardonable offence, where the difficulty of correct 

 discrimination is so much greater. I desire to have my names and 

 distinctive characters judged of by the strictest rules of zoology and 

 comparative anatomy ; and if I am not right, let others make me so. 



I beg leave to state here, however, that I do not base the names 

 which I propose upon a supposed knowledge of the true place of 

 the animals in the zoological scale ; but rather upon some peculiar- 

 ity of the feet, or supposed resemblance to known objects. So 

 that should the animals be shown by subsequent discoveries to be 

 very different from what I suppose them, still their generic and 

 specific names will be equally unobjectionable. 



The way is now prepared for enumerating and describing those 

 characters, derived almost wholly from their footmarks, by which I 

 propose to discriminate the lost animals that once trod the shores 

 of this country, and particularly of that ancient estuary which ex- 

 tended from Long Island Sound across Connecticut and Massa- 

 chusetts. 



1. Distinction hetiveen the thick-toed, or pachydactylous, and the 

 narrmv-toed, or leptodactylous, tracks, — This distinction is very 

 striking. The former show moulds or casts of toes, of great 

 width, with distinct claws and protuberances, corresponding, prob- 

 ably, to the phalanges. The latter class, with a few exceptions 

 belonging to intermediate species, probably, show very narrow 

 toes, in which neither claws nor phalangeal protuberances can 

 be distinguished. Sometimes the toes are very narrow, appear- 

 ing almost as if the mud had been impressed by the blade of a 

 knife ; certainly by a toe not thicker than those of some delicate 

 species of lizards. 



