Manual of human histology . lk. § 31LPhysiological remarks.—The lacteal gland, in its develop-ment, follows the same course as the other cutaneous glands,and is, as I find ( Mittheil. d. Ziircher nat. Gesells., 1850,No. 41) in accordance with Langer (1. c), originally (in thefourth to the fifth month) nothing but a solid papillary pro-jection of the mucous layer of the epidermis, which is investedby a layer of denser dermal tissue (fig. 273, i). In the sixthto the seventh month, it throws out acertain number of buds, and in thisway arise the first rudiments of thesubsequent lobes (fig. 273, 2)
Manual of human histology . lk. § 31LPhysiological remarks.—The lacteal gland, in its develop-ment, follows the same course as the other cutaneous glands,and is, as I find ( Mittheil. d. Ziircher nat. Gesells., 1850,No. 41) in accordance with Langer (1. c), originally (in thefourth to the fifth month) nothing but a solid papillary pro-jection of the mucous layer of the epidermis, which is investedby a layer of denser dermal tissue (fig. 273, i). In the sixthto the seventh month, it throws out acertain number of buds, and in thisway arise the first rudiments of thesubsequent lobes (fig. 273, 2). Theseare, at first, nothing but minute pyri-form- or flask-shaped processes of thecommon rudiment of the gland, whichdo not separate from each other un-til towards the end of foetal life, atwhich time they open externally;whilst, at the same time, roundedor elongated solid buds begin to ap-pear at their ends, which at this timeare also solid. At the period of birth,the gland measures from 1^—^, and already distinctly. Fig. 273. Development of the lacteal gland. 1. rudiment of the gland in a maleembryo, at five months: a, horny layer; 5, mucous layer of the epidermis; c, processof the latter or rudiment of the gland; d, fibrous membrane around the lacteal gland of a female foetus, at seven months, seen from above: a, centralsubstance of the gland, with larger (b) and smaller (c) solid outgrowths, the rudi-ments of the large gland-lobes. 276 SPECIAL HISTOLOGY. exhibits a certain number (12—15) divisions, of which theinternal still approximate the rudimentary papillce, in facthave either simple flask-like ends, or terminate in twoor three sinuosities; whilst the others are in connexionwith a greater number. The excretory duct of each of theserudimentary lobules, which is either simple or possesses twoor three branches, is composed of a fibrous membrane ofimmature, nucleated connective tissue, and an epithelium ofsmall cylindrical cells, and is manifestly hollow; w
Size: 1225px × 2039px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1850, booksubjecthistolo, bookyear1853
