. Text book of zoology. Zoology. 328 Vertebrata. fore-limb conforms to one type : articulating with the shoulder girdle by its upper end is a long bone, the humerus; to its lower end are attached two other long bones, the radius and ulna, together forming the fore-arm; at the proximinal end of the ulna there is usually a process, the olecranon, which projects over the radius. At the lower end of the fore-arm is the carpus (wrist), consisting, when completely developed, of two transverse rows of small cartilages or bones (carpals), three in the proximal, radiale, intermedium, ulnare, and five i
. Text book of zoology. Zoology. 328 Vertebrata. fore-limb conforms to one type : articulating with the shoulder girdle by its upper end is a long bone, the humerus; to its lower end are attached two other long bones, the radius and ulna, together forming the fore-arm; at the proximinal end of the ulna there is usually a process, the olecranon, which projects over the radius. At the lower end of the fore-arm is the carpus (wrist), consisting, when completely developed, of two transverse rows of small cartilages or bones (carpals), three in the proximal, radiale, intermedium, ulnare, and five in the distal row, one for each meta- carpal : a small bone or cartilage (or sometimes two) lies between these rows, the centrale. To the carpus, which undergoes many modifications, there are attached five (or fewer, rarely more) series of cartilaginous or bony pieces, of which the proximal in each row is termed a metacarpal, the others phalanges; whilst the metacarpals usually lie close together and are enclosed in a common skin, the digits are, for the most part, free. The pelvic girdle, like the shoulder girdle, is a paired or unpaired cartilaginous or bony arch, affording an articulation for the hind limbs. In Fish, it is independent of the vertebral column; but in other Vertebrata, it is almost invariably fused with one or more vertebrae, the sacrals, on either side. Like the shoulder girdle, each half is divisible, in all excepting Fish, into a dorsal portion, above the acetabulum (the point of articulation of the hind limb), the ilium, and a ventral piece which is, however, usually divided into anterior and posterior parts, pubis and ischium; the latter is usually articulated with the corresponding bone of the other side. Ilium, ischium, and pubis are always separate bones in young animals, and are connected by cartilage, of which, indeed, the whole pelvis originally consists; later, however, the three bones more or less completely fuse with one another. The skeleton of t
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1896
