A treatise on zoology . ^-- FlG. uMJ. Left pectoral girdle of Acipetiscf sturio. A, oblique view from behind. B, inner view.(From Gegenbaur, Vergl. Anaf.) cl, cleithram ; cV, clavicle; g, articular facets for pectoralfin-skeleton ; o, v, open channel ; »?, dorsal cartilage. growing edge of the fin-Aveb, sinking deeper into the connectivetissue, while the less numerous but more important lepidotrichia SKELETON 275 are formed outside them in the now more superfici;d layers (Fig. 343). Only in the fatty or adijoose fin of certain Teleostei (Salmonidae, Siluridae, r~~^^ ?/S^ ..»/ etc.
A treatise on zoology . ^-- FlG. uMJ. Left pectoral girdle of Acipetiscf sturio. A, oblique view from behind. B, inner view.(From Gegenbaur, Vergl. Anaf.) cl, cleithram ; cV, clavicle; g, articular facets for pectoralfin-skeleton ; o, v, open channel ; »?, dorsal cartilage. growing edge of the fin-Aveb, sinking deeper into the connectivetissue, while the less numerous but more important lepidotrichia SKELETON 275 are formed outside them in the now more superfici;d layers (Fig. 343). Only in the fatty or adijoose fin of certain Teleostei (Salmonidae, Siluridae, r~~^^ ?/S^ ..»/ etc.) do the actinotrichia acquire , , \ . >-i>^^ considerable size in the adult, and ^ -. / --^ - in these fins they form the sole \ ^^^-Tr^ 1^====^^23^ organs of support. ^T^.-^-^d^^^^l^^^^^^y). The skeleton of tlie pairedfins has already been discussedabove (p. 106), and will be furtherdealt with below (p. 302); butwe may here consider the structureof the limb-girdles. The endoskeletal pectoralgirdle consists of a bar of cartilage,extending dorsally as the scapularregion and ventrally as the cora-coid region (Figs. 241-3). Thetwo halves do not fuse ventrally,and as a rule are widely separated, resting on the dermal coveringbones (clavicle and cleithrum, p. 2U). Among living Teleostonu Fic. 243. IniiiT view of W\c. right half of the pectoral ginlle and tin of i<idiiin c, coracoid; , distal ,es ofradials; i/ic, mesocoracoid arch; ?-, tifthradial; ,s-, scapula ; , seaimlar furainen.
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
