The anatomy of the lymphatic system.

  • Klein, Emmanuel E.
Date:
1873
Catalogue details

Licence: Public Domain Mark

Credit: The anatomy of the lymphatic system. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    turn and pleura of all animals. They are not quite as numerous to be seen on the lymphatic capillaries of the mesentery of cat, monkey, and dog; but they occur relatively often in that of frog and toad. They are naturally extremely short, in consequence of the superficial position of the lymphatic capillaries, the membrane being very thin ; but they are in every case lined by a special layer of endothelium, which in every respect resembles that of those above mentioned. In these membranes—omentum, pleura mediastini and mesentery—■ stomata vera occur on lymphatic capillaries which accompany or in- vaginate the blood-vessels, as well as on those which have no such relation to the blood-vessels. It is necessary to mention that these stomata are generally not so very easy to demonstrate in the normal omentum, pleura mediastini, and mesentery (except that of the frog and toad), the lymphatic capillaries not being so easy to demon- strate. If, however, these membranes are slightly affected with chronic inflammation, their demonstration does not require any great skill; by spreading out the fresh membranes carefidly in serum they may be seen without further preparation. Exactly like the vertical lymphatic canals, i.e. stomata vera, just mentioned, are those of the septum cysternae lymphatica^ magnse of frogs and toads, described by Dogiel and Schweigger-Seidel. Different from the description given by these observers, I must mention that the vertical lymphatic canals are lined by a special layer of more or less polyhedral endothelial cells, which consist of a granular protoplasm. Accord- ing to D. and S. S., these stomata are bordered by the nuclei of the common flat large endothelial plates, both on the peritoneal surface and on that of the cystoma, which nuclei project into the stoma ; but these projections represent that special lining layer of polyhedral endothelial cells seen in profile, as it is easily to be recognised on membranes carefully spread out in the fresh state, and still better after staining with nitrate of silver. I refer the reader to Figiu-e 3, on Plate I. In female frogs and toads the endothelial lining of these vertical lymphatic canals is provided with cilite. In several female frogs and toads during the winter months I have found the endothelium of the stomata of the septum, as well as