Transactions . left ^The planes of these two sections form a sharply acute angle with eachother, as will be seen by an examination of Fig. i. ANATOMY OF THE ELEPHANTS EAR. 24T Eustachian tube, divided transversely at a point about tiveinches from its pharyngeal oritice. and slit up longitudinallythroughout a large part of its length. All the specimensare preserved in alcohol. The external auditory canal.—The auricle had been cutaway as close to the skull as possible, and all that remainsof the cartilaginous portion of the canal is represented bytwo overlapping, funnel-shaped gutters of cartila
Transactions . left ^The planes of these two sections form a sharply acute angle with eachother, as will be seen by an examination of Fig. i. ANATOMY OF THE ELEPHANTS EAR. 24T Eustachian tube, divided transversely at a point about tiveinches from its pharyngeal oritice. and slit up longitudinallythroughout a large part of its length. All the specimensare preserved in alcohol. The external auditory canal.—The auricle had been cutaway as close to the skull as possible, and all that remainsof the cartilaginous portion of the canal is represented bytwo overlapping, funnel-shaped gutters of cartilage, whichtogether form a complete conical framework around theskin-lined orifice of the external auditory canal. This ori-fice, which is nearly circular in shape, measures 9 millime-ters in diameter. It enters the skull in a direction nearlyparallel with the plane of the horizontal section. At a dis-tance of about 2 centimeters from the orifice, the canalbegins to bend downward in its course, and at the same. Fig. 1. Horizontal section of the slcull, a little above the level of the external audi-tory canal. To expose the latter throughout the greater part of its course, theupper wall of the bony cylimler has been chiseled away. (Reduced to one-thirdof the natural size of the parts.) time its calibre becomes considerably larger. At a dis-tance of 7 centimeters from the external orifice it measures 242 BUCK. 15 millimeters in diameter. In the vicinity of the mem-brana tympani the calibre of the canal again diminishes insize—to 9 or 10 millimeters, as nearl} as I could ascer-tain. The ring of cartilage, representing, so to speak, theinsertion of the auricle, loses itself in the cutaneous liningof the canal at a distance of about 5^ centimeters from theouter oritice. The entire length of the canal from theexternal orifice to the membrana tympani, measures 16^centimeters, or about 6}r inches. The skin lining the canal,for a distance of about 2 centimeters (| inch) from theorific
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Keywords: ., boo, bookcentury1800, bookdecade1860, booksubjectear, bookyear1868
