. Animal physiology. Physiology, Comparative; Physiology, Comparative. TRANSFERENCE OF SECRETING POWER. 281 accumulates in the blood (as in jaundice) is separated from it in the skin and conjunctival membrane of the eye (§. 537) '?> and milk has been poured forth from pustules on the skin, and from the salivary glands, kidneys, &c. Such cases have been re- garded as fabulous; but they rest upon good authority, and they are quite consistent with physiological principles. For a little consideration will show that, as the membrane which lines the stomach and intestinal tube is but a prolon
. Animal physiology. Physiology, Comparative; Physiology, Comparative. TRANSFERENCE OF SECRETING POWER. 281 accumulates in the blood (as in jaundice) is separated from it in the skin and conjunctival membrane of the eye (§. 537) '?> and milk has been poured forth from pustules on the skin, and from the salivary glands, kidneys, &c. Such cases have been re- garded as fabulous; but they rest upon good authority, and they are quite consistent with physiological principles. For a little consideration will show that, as the membrane which lines the stomach and intestinal tube is but a prolongation of that which forms the external surface of the body (§. 14), so the membrane that lines the tubes and follicles of which the glands are com- posed, is but a prolongation or extension of the former. Now we have seen that, in the lowest animals, the lining membrane of the stomach, and that which covers the surface, may be made to take the places of each other, without detriment to their respective operations (§. 14) ; and it is not incredible, therefore, that the various divisions of the secreting surface, which ordina- rily have separate duties to perform, should be able, under particular circumstances, to take on, to a certain degree, each other's functions. 362. Some of the main ducts or channels, through which the glands pour forth their secretions, are provided with enlarge- ments or receptacles, which serve to retain and store up the fluid for a time, until it may be desirable or convenient that it should be discharged. Thus, in most of the higher animals, the l duct which conveys into the intestinal tube the bile secreted by the liver, is also con- i nected with a receptacle termed the gall- bladder; the bile, as it is secreted, passes into this, and is retained there until it is wanted for assisting in the digestive process (§. 212); < when it is pressed out into the intestinal canal. It is a curious fact, that in most Fig. i6i.—urinary ap- persons who di
Size: 1204px × 2075px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcarpenterwilliambenja, bookcentury1800, bookdecade1840
