Fishes, 49 



covered with armour of thickly tuberculated bony plates, and both 

 fumished with a vertebrated tail." Our author compares Coccosteus 

 to a boy's kite, a simile which, from the figure,* appears sufficiently apt. 

 The arms are much more like fins or paddles than those of Pterich- 

 thys ; and indeed, exhibiting as they do an approach to the normal 

 form of a fish's fin, rather militate against the hypothesis already no- 

 ticed as suggested by Agassiz, that these organs in Pterichthys were 

 merely weapons of defence. The author, as well as many other geo- 

 logists, lays great stress on the similarity in outline between these 

 anomalous fishes and the extinct trilobites, thus hypothetically con- 

 necting the fishes with the Crustacea. It is not the province of a 

 notice like this to enter on so abstruse a question, but the premises on 

 which the hypothesis is founded, seem scarcely available in such a 

 cause. Let it be first solved whether a trilobite belonged to the 

 mollusk or crustaceous province of the animal kingdom, — whether 

 it crawled on its belly like a snail, darted through the water like a 

 shrimp, or ran on dry ground like a spider. After ascertaining these 

 particulars, let us attempt a comparison between it and other animals 

 by characters less superficial than mere outline or appearance, some- 

 thing a little more structural than the resemblance of an orchis to a 

 bee or a mantis to a leaf. Indeed Mr. Miller, although yielding to 

 the idea of thus connecting the fishes with the Crustacea, evinces a 

 much sounder mode of thinking when he speaks of the resemblance, 

 even when more striking, as '' pictorial.'''' After speaking of the body 

 of the trilobite as being really ']omieA, he tells us the body of Cepha- 

 laspis was barred by transverse scales, between which there were no 

 joints, and concludes his observations in these words. "It is interest 

 ing to observe how nature, in thus bringing two such different classes 

 as fishes and Crustacea together, gives to the higher animal a sort of 

 pictorial resemblance to the lower, in parts where the construction 

 could not be identical without interfering with the grand distinctions 

 of the classes." — p. 79. 



We are next introduced to fishes whose figure is somewhat more in 

 accordance with our notions of what a fish ought to be, yet differing 

 most essentially in some structural peculiarities. The readers of the 

 Zoologist must be well acquainted with the common sturgeon, and 

 must have observed the manner in which its head and sides are de- 

 fended with osseous plates: the same character is still more observ- 



* In our copy of the figure a portion of the tail has been drawn detached from ihc 

 body, in order to save the space which so long a block would have required. 



