108 ANALOGOUS TYPES. 



may not be easily traced. But the common 

 names used by the fishermen often indicate these 

 resemblances, as, for instance, Sea-Yulture, 

 Sea-Eagle, Cat-Fish, Flying-Fish, Sea-Porcupine, 

 Sea-Cow, Sea-Horse, and the like. 



In the branch of Mollusks, also, the same 

 superficial analogies are found. In the lowest 

 class of this division of the Animal Kingdom 

 there is a group so similar to the Polyps, that, 

 until recently, they have been associated with 

 them, the Bryozoa. They are very small ani- 

 mals, truly allied to the Clams by the plan of 

 their structure, but resembling the Polyps on 

 account of a radiating wreath of feelers around 

 the upper part of their body: yet, when exam- 

 ined closely, this wreath is found to be incom- 

 plete ; it does not form a circle, but leaves an 

 open space between the two ends, where they 

 approach each other, so that it has a horseshoe 

 outline, and partakes of the bilateral symmetry 

 characteristic of its type and on which its own 

 structure is based. These series have not yet 

 been very carefully traced, and young natural- 

 ists should turn their attention to them, and be 

 prepared to draw the nicest distinction between 

 analogies and true affinities among animals. 



