On food and its digestion: being an introduction to dietetics . e use of to mix with the food a variablequantity of a liquid poured largely into the mouth byvarious secreting organs, the salivary glands. Insalivation, as this act of admixture is termed, con-stitutes an important element of the digestive procesaHence the structures and secretions which effect it arecorrespondingly numerous and energetic. Three largeglands on each side:—the parotid, between the jaw andear; the sub-maxillary, behind and below the jaw, whereit adjoins the neck; and the sublingual, visible by raisingthe tip of the
On food and its digestion: being an introduction to dietetics . e use of to mix with the food a variablequantity of a liquid poured largely into the mouth byvarious secreting organs, the salivary glands. Insalivation, as this act of admixture is termed, con-stitutes an important element of the digestive procesaHence the structures and secretions which effect it arecorrespondingly numerous and energetic. Three largeglands on each side:—the parotid, between the jaw andear; the sub-maxillary, behind and below the jaw, whereit adjoins the neck; and the sublingual, visible by raisingthe tip of the tongue, as a crescentic swelling in front ofthis organ—constitute the chief sources of this addition, however, to these, there are numerous smallerglands, termed conglobate, from their ordinary shape,and of diameters varying from £rd to 2 or 2i lines,which raise the surface of the mucous membrane lining I^SALIVATIOX. 73 the mouth [into little swellings, named, according totheir situation, buccal, lingual, labial, and palatine glands. Fie. Conglobate oral gland, magnified 50 diameters. {After Koelliker.) a, Areolar investment; b, efferent duct; c, gland-vesicles; d, ducts of thelobules. The structure of all these glands is comparativelyuniform. The duct or canal by which each opens into the interiorof the mouth is of a width proportionate, in the main,to the total bulk of the gland of which it forms theconduit, and to that stream of secretion which it there-fore, at the period of greatest activity, has to convey. Its 74 DIGESTION. length, for reasons equally obvious, varies according tothe distance to which its orifice in the mouth is removedfrom the gland itself. But in spite of the great variationsthus permitted, the essential structure of all the salivaryglands is identical. Traced backwards from its terminalorifice, each has a duct, the thick wall of which perforatesthe mucous membrane by what is, in all but the smallestspecimens, a tube formed of muscu
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Keywords: ., bookauthorbrintonw, bookcentury1800, bookdecade1860, bookyear1861
