NOTES ON THE SALMO SALAR SPECIMEN — MORROW. 183 



pelvic bones. The bony plates to which are attached the ven- 

 tral fins, together with the fins are usually called the pelvic 

 limbs, but it appears to me there can be little doubt that the so 

 called pelvic bones with the fins are the representatives of the 

 hind legs of mammals, thus : 



The saddle bones and the bone with the cup-shaped orifices 

 below them, are the pelvic bones. 



The centra without spinous processes, the sacral vertebrae. 



The large hypural bone, the femur. 



The pelvic bones, or the bony plates to which the fins are at- 

 tached ; the tibia and fibula and the ventral fins generally the 

 feet. 



The Shoulder girdle and Pectoral fins. 



At the junction of the body with the head under the opercular 

 plate, appears on each side of the fish a series of bones forming 

 the fore frame and support of its body, and from which spring 

 at about two-thirds of their total length the pectoral fins. In the 

 specimen of the salmon before you on their outer sides each set ap- 

 pears primarily to be formed of three bones. Reversing these bones 

 and looking at their inner surfaces there appears to be on each 

 division (right and left side) another bone now anchylosed 

 with the posterior edges of each middle bone or inter-clavicle, 

 and throwing off from their anterior edges a thin process or 

 plate, which passes partially over the lower edges of the 

 supra-clavicles and united to the anterior edge of each of the 

 inter-clavicles, serving as a base for the supra-clavicles and for 

 the attachment of their tissues. 



Taking, as in the ventral fins, the shoulder girdle, left side — 

 removed from the body of the fish, the upper portion the supra- 

 clavicle viewed from the outside has a two -fold* termination, the 

 posterior fork passes freely, apparently without any ligamentousf 

 attachment, into the fleshy tissue ; measured in a direct line from 

 base to point it is 2^ inches in length, and its base is a little 

 less than § of an inch in breadth. It overlaps the inter- 

 clavicle ; at | of an inch from its base, anteriorly, arises 



* Three-fold, if looked upon as the same bones in the cod are usually accepted, 

 t I could not find any in three specimens. 



