BY DR. KLEIN. 131 



days, it is possible to make thin sections of small extent. It is 

 easier, however, to make sections of glands which have been 

 steeped two or three days in common alcohol. The sections, 

 stained or unstained, are placed two or three together in a test 

 tube, half full of water, which must then be shaken regularly 

 but briskly until the sections acquire the characters of reticu- 

 lated membranes. The contents of the test tube are poured 

 into a shallow capsule, and prepared in the usual manner, 

 either for mounting in Dammar varnish or glycerin. It is well 

 not to continue the agitation longer than is necessary to get 

 rid of the medullary substance of the gland. The globular or 

 ovoid follicles which constitute the mass of the cortical sub- 

 stance, and are in continuity with the lymphatic cylinders, are 

 seen in such preparations to have the following structure : 

 Each consists of a close network of fibres, the meshes of which 

 are of nearly equal size. It is further seen that the fibres are 

 thickened at the nodes, and that each thickening contains a 

 nucleus. The younger the animal, the more obvious it is that 

 the network consists of branched cells. The follicle also con- 

 tains numerous capillaries. From the network of branched 

 cells which forms the adventitia of each capillary, spring fila- 

 ments which either stretch to neighboring capillaries, or form 

 a part of the general adenoid network of the follicles. These 

 filaments are alwaj's broader at their bases than elsewhere, 

 and have thickenings which contain nuclei. In sections which 

 have not been agitated, the whole network is filled with small 

 roundish bodies (so-called lymph corpuscles). It can be readily 

 shown in glands which are injected from the lymphatics, that 

 each follicle is surrounded by sinuses, which are mere dilata- 

 tions of the different lymphatic vessels of the cortex, and are 

 in like manner lined with endothelium, as is seen in glands in- 

 jected with nitrate of silver. Outside of the follicles is a layer 

 of connective tissue which contains numerous bloodvessels, and 

 is continuous towards the hilus, with the trabeculse, which form 

 the framework of the organ. Outwards it is intimately united 

 with the capsule. In glands of which the bloodvessels are in- 

 jected, capillary loops can be seen to penetrate into the follicles 

 from the rich network of bloodvessels with which each is in- 

 vested. The part of the gland between the cortical substance 

 and the hilus consists of lymphatic cylinders, and intervening 

 trabeculae. The former are united with each- other so as to 

 form a network, and have the same intimate structure as the 

 follicles, as regards the adenoid network, the cells it contains, 

 and the capillaries. In general they possess only capillaries ; 

 occasionally, however, larger vessels enter them. The trabe- 

 culae consist of fine fibres which run mostly parallel to each 

 other; they are connected into a meshwork, the intervals of 

 which are occupied by the network of cylinders. There are, 



