ANATOMY OF VERTEBRATES. 



93 



Anatomy. Without knowing the what, the how, and the ichy, 

 one may stand, not for hours or days, but weeks, before a fish's 

 skull, and our contemplation will be little more than a vacant 

 stare at its complex stalactitic form.' 



To show what the bones are that enter into the composition of 

 the skull of the fish ; how, or according to what law, they are there 

 arranged ; and why, or to what end, they are modified, so as to 

 deviate from that law or archetype, will next be our aim. These 

 points, rightly understood, yield the key to the composition of the 

 skull in all vertebrata, and they cannot be omitted without detri- 

 ment to the main end of the most elementary essay on the 

 skeletons of animals. The comprehension of the description will 

 be facilitated by reference to figs. 75 — 85 ; and still more if the 

 reader have at hand the skull of any large fish. 



In the Cod ( Gadus morrhua, L. fig. 75), e. g., it may be observed, 

 in the first place, that most of the bones are, more or less, like 



Skull of Cod {Morrhua vulgaris), Cuv. 



large scales ; have what, in anatomy, is called the e squamous ' cha- 

 racter and mode of union, being flattened, thinned off at the edge, 

 and overlapping one another ; and one sees that, though the skull, 

 as a whole, has less freedom of movement on the trunk, more of 

 the component bones enjoy independent movements. Before we 

 proceed to pull apart the bones, it may be well to remark, that the 

 principal cavities, formed by their coadaptation, are the ' cranium,' 



