Descriptive and Illustrated Catalogue of the Histological Series Contained in the Museum of the Royal College of Surgeons of England Volume 1 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1850 Excerpt: ...a number of circular follicles, some empty, others full of a darkgranular material; in the cuticular layer may be observed numerous small stellate pigment cells, which are arranged so as to form a network composed of two sets of rings, one set being situated around the follicles above alluded to, and the other around the interspaces between the follicles; the latter are of smaller size than the former, and are evidently follicular; they appear as so many white spots when only a superficial examination is made of them. The arrangement of the pigment cells above described exists only in darkest parts, and may be said to be perfect; but if the lighter portions be examined, the cells will be found both Y2 fewer in number and quite circular, but they exhibit a similar order of deposition to those more perfectly developed. To the naked eye, the masses of pigment cells give the skin a marbled appearance, and in those parts in which it is absent the follicular structure can be observed. A n 7. A preparation of the skin of the same Newt, exhibiting a much larger collection of the pigment cells; in some of the darkest spots, the cells not only surround the margins of the follicles, but their branches radiate towards the centre of each, so as to give it an inner margin of a lighter brown colour than the outer one. A n 8. A portion of the web of the foot of a Frog, Rana temporaria, exhibiting numerous pigment cells, mostly of a stellate figure; in this part of the body they are not collected into masses as in the Newt, but generally occur singly. A n 9. A portion of the skin of the tadpole of a Frog, exhibiting stellate pigment cells of larger size than those in the preceding specimen; they closely resemble the cells of the Lamprey, Trout, and fishes generally. A n 10....