. Principles of human physiology : with their chief applications to pathology, hygiene, and forensic medicine : especially designed for the use of students. termination in thenipple, and then ramifying like the roots of a tree, their ultimate subdivisionsterminating in minute cells. The mamillary tubes are usually about ten ortwelve in number; they are straight ducts, of somewhat variable size; andtheir orifices, which are situated in the centre of the nipple, and are usuallyconcealed by the overlapping of its sides, are narrower than the tubes them-selves. At the base of the nipple, these tub
. Principles of human physiology : with their chief applications to pathology, hygiene, and forensic medicine : especially designed for the use of students. termination in thenipple, and then ramifying like the roots of a tree, their ultimate subdivisionsterminating in minute cells. The mamillary tubes are usually about ten ortwelve in number; they are straight ducts, of somewhat variable size; andtheir orifices, which are situated in the centre of the nipple, and are usuallyconcealed by the overlapping of its sides, are narrower than the tubes them-selves. At the base of the nipple, these tubes dilate into reservoirs, whichextend beneath the areola and to some distance into the gland, when thebreast is in a state of lactation. These are much larger in many of thelower Mammalia, than they are in the Human female; their use is to supplythe immediate wants of the child when it is first applied to the breast, so thatit shall not be disappointed, but shall be induced to proceed with suckinguntil the draught be occasioned (§ 426). From each of these reservoirscommence five or six main branches of the lactiferous tubes, each of which Fig. Distribution of the milk-ducts in the Mamma of the human female, during lactation; the ductsinjected with wax. (Alter Sir. A. Cooper.) speedily subdivides into smaller ones, and these again divaricate, until theirsize is very much reduced, and their extent greatly increased. The propor-tional size of the trunk and of its branches appears to follow the same lawwhich governs that of the blood-vessels. The breast is not formed into regu-lar lobes by the ramifications of the ducts; because they ramify between,and intermix with, each other, so as to destroy the simplicity and uniformity SECRETION OF MILK. 525
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Keywords: ., bookcentury1800, bookdecade1840, bookpubli, booksubjectphysiology
