TRILOBITE HUNTING. 215 



These many slight resemblances to other animals, 

 whatever they may suggest as to descent and modifi- 

 cation, do certainly show how large a portion of the 

 crustacean area was occupied by trilobites all through 

 the vast ages of palaeozoic time. From the king- 

 crab to the shrimp-parasite is a long distance, and 

 yet trilobites by their varied functions and organs 

 evidently stretched out over that distance; and 

 though nothing absolutely conclusive can be inferred 

 in regard either to the origin or the descent of the 

 trilobite, yet these numerous affinities afford a field 

 extensive enough for the speculations of the most 

 imaginative and the inquiries of the most in- 

 dustrious. 



