so COilPARISONS OF STRUCTURE IN ANIJIALS. 



have the scapula, the clavicle, the two bones of 

 the fore-arm, and the hand, divided into rays. 

 Cuvier, however, regards the two bones forming a 

 rude fore-arm, as really belonging to those which 

 enter into the wrist at the base of the hand. 

 The ventral fins are placed far anterior to 

 the pectoral, and the gills inclose a large 

 chamber, with only a small opening behind 

 the latter fins, and are consequently capable 

 of containing a supply of water, should it 

 be needed. Mr. Yarrell, in his History of 

 British Fishes, says : "The ventral fins, palmate 

 in form, are placed very far forward on the 

 body, and the pectorals, from their position, 

 perform the office of hinder feet." "Upon the 

 head are two slender, elongated aj^i^endages, 

 the first of them broad, and flattened towards 

 the end, and having, at this dilated part, a 

 shining, silvery appearance. These elongated 

 filaments are curiously articulated at the base, 

 with the upper sm'face of the head ; they have 

 great freedom of motion in any direction, 

 the first filament more particularly, produced 

 by numerous muscles, amounting, according to 

 M. Bailly, to twenty-two!" 



It will be interesting here to show how the 

 structure of the limbs of this large and terrific 



