. A manual of zoology. Zoology. Fig. 566.—Lateral and hinder views of frog skull fafter Parker). Letters for this and 565: qh, angulare; As, alisphenoid cartilage; co (Cocc), occipital condyles; col, columella; d, dentary; E (e), sphenethmoid; fo, foramen magnum; FP, fronto- parietal; Gk, otic capsule; h', h", hyoid and copula; jg, jugal; M (m), maxillary (in lower jaw mento-Meckelian); mk, Meckel's cartilage; N, TV', nasal capsule; na, nasal; oh, OS, cartilages from which basi- and supraoccipitals arise elsewhere; ol (Olat), cipital; pf, frontoparietal; Pal, palatine; p (PP), pala
. A manual of zoology. Zoology. Fig. 566.—Lateral and hinder views of frog skull fafter Parker). Letters for this and 565: qh, angulare; As, alisphenoid cartilage; co (Cocc), occipital condyles; col, columella; d, dentary; E (e), sphenethmoid; fo, foramen magnum; FP, fronto- parietal; Gk, otic capsule; h', h", hyoid and copula; jg, jugal; M (m), maxillary (in lower jaw mento-Meckelian); mk, Meckel's cartilage; N, TV', nasal capsule; na, nasal; oh, OS, cartilages from which basi- and supraoccipitals arise elsewhere; ol (Olat), cipital; pf, frontoparietal; Pal, palatine; p (PP), palatine arch; Pmx, ; Pro, prootic; Ps, parasphenoid; Pt, pterygoid; Qu, quadrate; Qjg, jugal; sq, squamosal; Vo, vomer. Cartilages dotted. tion of the quadrate into a suspensor the hyomandibular loses its function, and if represented at all, it is as part of the columella. The character of the remain- ing visceral skeleton depends upon the respiration (fig. 567). Where gills occur, the copula and hyoids—representing body and cornua—as well as four gill arches are present, but with pulmonary respiration the hyoid apparatus is reduced to a hyoid with anterior and poste- rior cornua, the gill arches being contained in the posterior horns. To understand the conditions in the higher vertebrates it must be remembered that the reduced fifth arch becomes a support of the larynx and that in many anura the hyoid extends to the skull and fuses with the otic capsule. With the assumption of a terrestrial life changes occur in the sense organs. The organs of the lateral line, which occur in all larvje and are persistent in the aquatic perennibranchs, and the nerves which supply them, disappear; the eyes in the Salamandrina have upper and lower lids; in the frogs an mider lid (really nictitating mem- brane). The nose becomes respiratory and is provided with choanas opening into the mouth. Especially noteworthy is the auditory appa- ratus. This, in the urodeles and cjecilians, i
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1912
