The Hemolymph Nodes of the Sheep Volume 16 (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. 1914 Excerpt: ...present, around very small blood islands. Moreover, whenever the total amount of blood was larger the contiguous surfaces of blood and lymphatic tissue were often indicated by a gently curving line, instead of by a very irregular and ill-defined one. However, here and there a portion of lymphatic tissue of irregular form might nevertheless extend boldly out into the surrounding blood. It is only occasionally that blood islands are found within the follicles; and when so found they are generally small, and never seem to be continuous with those outside of them. Nevertheless their absence rather than their presence here would seem to need an explanation. In addition to the large venous spaces in direct communication with the vein, usually located near the center of the node, when present, there are small and more numerous ones, termed venous lacunae" by Weidenreich 37. These dilated empty, or nearly empty, spaces are apparently most numerous and conspicuous In nodes which contain much more blood than lymphatic tissue (figs. 17 and 19). Indeed in such nodes they are frequently so numerous, so large, and so devoid of celluar content that they may give an almost fenestrated appearance to a section. In these specimens--and in general, for that matter--they are most evident near the periphery (figs. 8 and 11). In depleted nodes this fact can, to be sure, be easily accounted for by the fact that most of the remnants of the lymphatic tissue are for some reason found in this location (fig. 18); but why they should be more evident here than elsewhere in the more typical nodes (fig. 8) is not so obvious. Although the configuration of these lacunae or true venous sinuses is an extremely irregular one, and although their boundaries are not always well defined, it wa...