. Quain's elements of anatomy . they are still more abundant,and of greater size, in the circumvallate papillas, where they are chiefly dis-tributed in the neighbourhood of the taste-buds (fig. 492). The papillae, besides being the parts chiefly concerned in the special sense oftaste, also possess, in a very acute degree, tactile sensibility; and the conical andfiliform papillfe, armed with their denser epithelial coveiing, serve a mechanicalpurpose, in the action of the tongue upon the food, as is well illustrated by themore developed fonn which these papillse attain in many carnivorous anima
. Quain's elements of anatomy . they are still more abundant,and of greater size, in the circumvallate papillas, where they are chiefly dis-tributed in the neighbourhood of the taste-buds (fig. 492). The papillae, besides being the parts chiefly concerned in the special sense oftaste, also possess, in a very acute degree, tactile sensibility; and the conical andfiliform papillfe, armed with their denser epithelial coveiing, serve a mechanicalpurpose, in the action of the tongue upon the food, as is well illustrated by themore developed fonn which these papillse attain in many carnivorous animals. Glands.—The mucous membrane of the tongue is provided withnumerous small glands {Ungual glands), collected principally about theposterior part of its upper surface, near the papillae vallatte and foramenc£ecum, into -niiich last the ducts of several open. These glands haveusually been supposed to secrete mucus, but it has been ascertained thatsome of them, especially those which open in the trenches around the Fiff. Fig. 497.—Section of a lym-phoid CRYPT FROM THE ROOTOF THE TOXGUE. 30 DIAMETERS. (Kolliker.) a, epithelial lining ; 5, papillaeof the mucous membrane; c, outerpart of the crypt, formed of con-nective tissue ; d, outlet, and e,cavity of the crypt; g, surround-hvx follicles. papillae vallatse, and at other parts where taste-buds occur, yield a morewatery secretion (Ebner). Other small glands are found also beneaththe mucous membrane of the borders of the tongue. There is, inparticular, a group on the under surface of the tongue on each side nearthe apex. They are there aggregated into a small oblong mass, out ofwhich several ducts proceed and open in a line on the mucous of the glands are racemose ; others acino-tubular. The mucous membrane of the tongue, at least its posterior part, islargely .composed of retiform or lymphoid tissue, which is collected atnumerous points into the denser nodular masses known as follicularglands, or lymphoid
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Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
