Buckmaster's Elements of animal physiology / by John Angell.

  • Angell, John
Date:
1866
Catalogue details

Licence: Public Domain Mark

Credit: Buckmaster's Elements of animal physiology / by John Angell. Source: Wellcome Collection.

    328/384 (page 316)
    minate in the papilla previously described. In certain parts the sensibility is intensified by the tactile bodies, resembling the Pacinian corpuscles previously referred to in Fig. 51 (page 256). A, represents the body of the corpuscle, consisting of 30 to 60 distinct concentric laminae or capsules; B, E, the interior cavity into which the nerve tube passes; C, its stalk, consisting of modified neurilemma; D, the nerve tube, passing up the stalk to the axis of the capsule. Considerable difference of opinion as to their structure and functions prevails among physiologists. The Sense of Taste resides chiefly in the tongue, but is not entirely confined to that organ; the soft palate, the arches of the palate, and the fazices partici- pating, though much more feebly, in that function. The tongue is the principal organ of taste and speech; it is almost entirely composed of muscular fibre ; it has a dorsum (back), tip, edge, or border, and is divided by a 7nedian line, on its upper surface, into two symme- trical halves. Its exterior is lined with mucous mem- brane, covered with epithelium, which becomes thick and matted or furred, when the stomach is disordered. Its upper surface is covered with papilla, which comprise three varieties:—r. Filiform (threadlike), which are most numerous. 2. Fungifomn (mushroom- shaped). 3. Circumvallate (from L., circum, round; and vallo, I dig), which consist of a central mowid or club-shaped process, surrounded by a circular excava- tion, trench, or furrow. The number of the latter, which are situated in two oblique rows at the base of the tongue, does not usually exceed eight or ten. The three varieties just described are termed compound papillae; they are covered by smaller papillae termed secofidary; the latter are also termed simple papillae. The papilla and surface of the tongue are supplied