PISHES. '.iO'i 



To the internal lamina of this third Lone, adhere a fourth (No. 51), 

 and a fifth (No. 52), placed over each other, and each pierced by a 

 hole, or laterally fissured, and thus maintained in connexion with the 

 preceding bone. This fissure most commonly gives to the infei - ior 

 of the two bones the form of a square. Their free side supports the 

 pectoral fin, but it is by an intermediate range of four or five minute 

 bones (No. 53), placed between these two bones and the rays of the 

 fin, the first ray excepted, which is immediately connected -with the 

 superior bone (No. 52). 



These minute bones recall to us most strikingly the recollection of 

 the bones of the carpus ; and, if this comparison be just, then the two 

 pieces (Nos. 51, 52) to which the minute bones adhere, will repre- 

 sent, as we have before suggested, the ulna (No. 51), and the radius 

 (No. 52). 



The third bone of the girdle, the great inferior bone which sup- 

 ports the two latter, will correspond then necessarily with the 

 humerus, and the first and second (Nos. 46, 47) will represent the 

 scapula. In short, the scapula of several reptiles, particularly that of 

 the frog, is manifestly composed of two osseous pieces, and even 

 there the superior is frequently bifurcated, as it almost always is in 

 fishes. 



Henceforth we shall distinguish the two superior pieces of the 

 girdle by the names superscapulary * and scapulary\ ; the third will 

 be our humeral,]; and the two which bear the fin, shall be our ulnar 

 and our radial. § 



In some genera, but conspicuously in the salmons and in the 

 cyprins, these two latter bones have, upon the internal side of their 

 suture, a third bone, of which the extremity opposite to that which is 

 attached to these bones, supports itself against the anterior border of 

 the humerus, and thus acts as an arched buttress. 



In the silures these three bones become very quickly soldered toge- 

 ther, and even with the humerus, probably on account of the effort 

 which they must make to support the very large spinous ray of the 

 pectoral. 



In the eels, where there are only two of these bones, they are in a 

 condition, as if suspended to the point of junction of the scapular and 

 humeral bones, and they are no longer to be seen in those species of 

 fishes, where the pectoral is deficient. 



A sort of stylet remains which is almost invariably composed of 

 two pieces (Nos. 49, 50) ; the superior piece (No. 49), which is 



* M. Bakker calls the superior bone the scapula, it is the omolite of M. Geoffroy, 

 I have called it for a long time the pedicle of the shoulder. 



f This is the scapula; of Geoffroy, and the acromion of M. Bakker. 



X Gouan calls this bone the clavicle. In point of fact it does perform the 

 functions of one up. to a certain extent, and M. Geoffroy has ultimately adopted this 

 name. M. Bakker, considering it to be the clavicle and humerus incorporated, calls 

 it coenosteon. M. Meckel calls it simply the clavicle, and so does M. Geoffroy. 



§ These bones have been already called thus by M. Bakker. M. Geoffroy, 

 however, takes our ulnar for a humerus, and does not speak at all of a radius, 

 at least not distinctly. In lophius and polypterius he considers the bones of the 

 carpus as those of the fore arm. 



VOL. II. X 



