. Elementary text-book of zoology. Zoology. THE SYKJ NX. 249 osseous band—the jn'.^/'fn/i—whirli forms a vertical septum between the anterior apertures of the t\v bronchi. This septum, at its anterior (ventral) and posterior (dorsal) ends, gives oil.' on each side two arched processes, which pass downwards—one along the dorsal, and the other along the ventral edge of the bronchus of its side; and between these cornua the internal wall of each bronchus, which is here membranous, is stretched, and constitutes the membrana internet,. In the Singing Birds there is in addition a sem
. Elementary text-book of zoology. Zoology. THE SYKJ NX. 249 osseous band—the jn'.^/'fn/i—whirli forms a vertical septum between the anterior apertures of the t\v bronchi. This septum, at its anterior (ventral) and posterior (dorsal) ends, gives oil.' on each side two arched processes, which pass downwards—one along the dorsal, and the other along the ventral edge of the bronchus of its side; and between these cornua the internal wall of each bronchus, which is here membranous, is stretched, and constitutes the membrana internet,. In the Singing Birds there is in addition a semi-lunar fold (iiii'n)l>ran</< xi'iii!ltt,it—is developed a. FIG. 657. — Lower larynx of Raven (from Owen). «, Side view of larynx laid open.— i, Larynx after removal of muscles. — c, Larynx with muscles, from the front ; J, from the side. St, pessulus. ; Mfy, membrana tyinpaniformis iiiterua; J/>, membrana semilunaris; Sf, modified last tracheal riusj ; Rlj, the modified three first bronchial rin^s ; -I/, muscles. on the external side of the tympanum, and forms with the free edge of the internal tympaniform membrane (, with the semilunaris), a vocal slit or glottis on either side. The tension of these folds, which function as vocal cords, is regulated by a muscular apparatus, which connects the trachea with the lateral parts of the tympanum, or also with the anterior bronchial rings, and is most highly developed in the singing birds, in which the syrinx may possess live or six pairs of such muscles. The bronchi are relatively short and lead, at their entrance into the lungs, into a number of wide membranous bronchial tubes, which traverse the pulmonary tissue. The lungs are not, as in Mammals, freely suspended in a closed thoracic cavity and invested. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resembl
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
