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MANUAL OF ZOOLOGY. 



strengthened by bony or cartilaginous fin-rays. The anterior 

 limbs are known as the pectoral fins, and the posterior as the 

 ventral fins; and they are at once distinguished from the 

 so-called " median " fins by being always symmetrically dis- 

 posed in pairs. Hence they are often spoken of as the paired 

 fins. The scapular arch (figs. 127, 128) supporting the pec- 

 toral limbs is usually joined to the skull (occipital bone), and 

 consists of the following pieces on each side : i. The supra- 

 scapula (ss) ; 2. The scapula (s), articulating with the former; 

 and, 3. The coracoid (co) y attached above with the scapula, and 



c u 



Fig. 128. Pectoral limbs of Fishes (after Owen). A, Cod (Morrhua vulgaris) ; B, 

 Angler (Lophius). ss Supra-scapula ; s Scapula ; co Coracoid ; r Radius ; Ulna ; 

 cc Carpal bones ; f Fin-rays, representing the metacarpus and phalanges of the 

 fingers. 



united below, by ligament or suture, with the coracoid of the 

 opposite side, thus completing the pectoral arch. Lastly, there 

 is often another bone, sometimes single, but oftener of two 





