. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OSSEOUS SYSTEM. (COMP. AN.\T.) 835 attached to the extremity of the upper poition of one of the thiee last branchial arches. Condition oft/icos liyoidcs in Reptiles.—The condition of the os hyoides in a per- fect Reptile is very simple when compared with that of the Fish, or even, as is most strikingly apparent in the amphibious Reptilia, with that which it exhibits previous to the accomplish- ment of the metamorphosis which changes the mode of respiration from that ofa fish inlo that of the Frog. In the adult Reptile, i
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OSSEOUS SYSTEM. (COMP. AN.\T.) 835 attached to the extremity of the upper poition of one of the thiee last branchial arches. Condition oft/icos liyoidcs in Reptiles.—The condition of the os hyoides in a per- fect Reptile is very simple when compared with that of the Fish, or even, as is most strikingly apparent in the amphibious Reptilia, with that which it exhibits previous to the accomplish- ment of the metamorphosis which changes the mode of respiration from that ofa fish inlo that of the Frog. In the adult Reptile, indeed, the composition of this bone gives no indication of its pre- vious complexity of struc- ture, consisting only of the remains of the anterior cor- nua (26, a) and a broad hatchet-shaped disc forming the body of the bone. In Lizards its structure remains more complicated, resembling that of Birds. The body is generally simple, with two and sometimes three sets ofcormia- like appendages connected with it. From the fore part of the body projects along and slender process, more or less cartilaginous, which pe- netrates the substance of the tongue. The ante- rior pair of cornua are variously folded, and the posterior placed differently in different genera; while the third pair, which is but seldom met with, seem rather to be prolongations of the body of the bone than separate elements appended to it. In theChelonian Reptiles the hyoid apparatus varies remarkably in form in different species. It generally consists of a central part, which is frequently itself divisible into several pieces, and of two or sometimes three pairs of cornua. Moreover, beneath the anterior part of the body, there is suspended a bone or cartilage, which is sometimes double and represents the special bone of the tongue, which in Birds is articulated to the fore part of the body of the os hyoides. The os hyoides of the Crocodiles is the sim- plest met with in the class of Reptiles, its central portion
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