116 ESSAY ON CLASSIFICATION. Part I. 



of every class may then be considered as embryonic types of their respective orders 

 or fliraihes among the living. Pedunculated Crinoids are embryonic types of the 

 Comatuloids, the oldest Echinoids embryonic representatives of the higher living 

 families, Trilobites embryonic types of Entomostraca, the Oohtic Decapods embryonic 

 types of our Crabs, the Heterocercal Ganoids embryonic types of the Le^^idosteus, 

 the Andrias Scheuchzeri an embryonic prototype of our Batrachians, the Zeuglodonts 

 embryonic Sirenidae, the Mastodonts embryonic Elephants, etc. 



To appreciate, however, fully and coiTCctly all these relations, it is further neces- 

 sary to make a distinction between embryonic types in general, which represent 

 in their whole organization early stages of growth of higher representatives of the 

 same type, and emhijonic features prevailing more or less extensively in the charac- 

 ters of allied genera, as in the case of the Mastodon and Elephant, and what I 

 would call Jii/pemhri/onic types, in which embryonic features are developed to extremes 

 in the farther periods of growth, as, for instance, the wings of the Bats, which 

 exhibit the embryonic character of a webbed hand, as all Mammalia have it at 

 first, but here grown out and developed into an organ of flight, or assuming in 

 other families the shape of a fin, as in the Whale, or the Sea-turtle, in which the 

 close connection of the fingers is carried out to another extreme. 



Without entering into further details upon this subject, which will be fully 

 illustrated in this work, enough has already been said to show, that the leading 

 thought which runs through the succession of all organized beings in past ages, is 

 manifested again in new combinations, in the phases of the development of the 

 living representatives of these different types. It exhibits every^vhere the working 

 of the same creative Mind, through all times, and upon the whole surface of the 

 globe. 



SECTION XXVI. 



PROPHETIC TYPES AMONG ANIMALS. 



We have seen in the preceding paragraph, how the embryonic conditions of 

 higher representatives of certain types, called into existence at a later time, are 

 typified, as it were, in representatives of the same types, which have existed at 

 an earlier period. These relations, now they are satisfiictorily known, may also be 

 considered as exemplifying, as it were, in the diversity of animals of an earlier 

 period, the pattern upon which the phases of the development of other animals 



