196 PISCES. 



formed for the metacarpus. To these bones are appended the digital 

 articulations or fin-rays (radii .pinna pectoralis}, which form the sup- 

 porting frame-work of the pectoral fins. 



The varieties in the construction of the anterior extremities in the 

 several genera are very great. The arrangement in the Eel is of a 

 very simple kind, there being a single bone or scapula not bifurcated, 

 and below that the clavicular bone. In addition to these are two 

 bones for the second division, and several for the carpus and the 

 fin-rays. The bones are somewhat more developed in Gymnotus, 

 where the scapula is united to the skull. The genera Exocaetus, 

 Lophius, Silurus, Tetrodon, possess also but one bone for the scap- 

 ula ; most of the Osseous Fishes, e. g., Perca, Esox, Cyprinus, Cy- 

 clopterus, Trigla, Scomber, Chaetodon, Gadus, Brama, &c., are pro- 

 vided with two, an anterior and posterior, clavicular bones, two to 

 three brachial, three to four carpal bones, and next in succession 

 with fin-rays or phalanges ; many, as several species of Scieena, 

 Spams, Labrus, &c., have as many as three scapular bones ; the 

 posterior or coraco-clavicular bone is absent in Anarrhicas, Silurus, 

 Uranoscopus, Fistularia, Exocaetus, arid consists invariably of only 

 a single bony piece in Cyprinus, Esox, Batrachus, Lophius, and 

 Chironectes ; in Chsetodon it abuts against the bones of the pelvis ; 

 in Zeus the two clavicles coalesce inferiorly ; the carpus in Lophius 

 and Chironectes is formed of two very long bones, that have been 

 falsely compared with the ulna and radius ; in Batrachus there are 

 five similar bones, aud in Polypterus two elongated bones, with one 

 or several discoidal ossicles interposed between them ; this Fish has 

 also, as an occasional peculiarity, a row (amounting even to 18) of 

 elongated bones, which correspond to the metacarpus. The carpal 

 bones are very seldom wanting, as in Exocaetus (where the fin-rays 

 are remarkably long) and in Uranoscopus. For the second or ante- 

 brachial division of the anterior extremity we find, in Silurus and 

 Heterobranchus, only one bone ; the first fin-ray is, on the contrary, 

 strong and linked to the anterior clavicular bone ; so that here, as in 

 Pimelodes, Platycephalus, and others, it is very broad inferiorly. and 

 united with that of the opposite side by a zigzag suture. 



The Pelvis and Posterior Extremities are but very rudimentary in 

 the Osseous Fishes, and not connected to the vertebral column, but 

 are imbedded simply in the flesh, as in the Amdominales, or abut 

 against the anterior clavicular bones, as in the Thoracici and Jugu- 

 lares ; occasionally they are completely wanting, or we find in their 

 place two usually long flat bones, which support on their posterior 



