CT. 218.] ON THE LYMPHATIC GLANDS. 5 13 



to be regarded as the proper place of formation of the lymph-corpuscles, 

 though I do uot mean to deny that similar processes may take place in the 

 medulla also. In the alveoli of the cortex, with their peculiar anatomical 

 arrangements, the entering lymph comes most intimately into contact with 

 the numerous blood-vessels. Now since the pressure to which the blood is 

 subjected is, in any case, much more considerable than that which is exerted 

 upon the lymph, many constituents of the blood will pass out here into the 

 lymphatic lacunae and mingle with the lymph; and as the lymph in this 

 lacunar system is meanwhile moving very slowly, every opportunity is given 

 for the formation of cells. The exudation from the blood-vessels obviously 

 plays a much more important part in this process, than the slow movement 

 of the juice itself, and I am of opinion, that if the former were removed the 

 multiplication of the lymph-corpuscles in the glands would not be consider- 

 able. For when we consider that the lymph from vessels which have not 

 passed through glands is always very poor in corpuscles, no matter whether 

 it has gone over a short or long distance ; and again, that the lymph of 

 those vertebrate animals which possess only a few isolated lymphatic glands, 

 or none at all, is very poor in cells, we shall arrive at the conviction, that 

 the lymph is of itself but little capable of organisation, even when it has 

 gone over a considerable distance, and that the formation of the colourless 

 cells in the lymphatic glands is chiefly dependent upon the transuding con- 

 stituents of the blood. The processes, therefore, in the lymphatic glands 

 may more correctly be expressed by saying that a continual exudation of 

 certain constituents of the blood takes place from the blood-vessels into the 

 lymphatic lacunae, and from this there results an abundant formation of 

 cells which fill the lacunae. The entering lymph with its scanty cells now 

 become mingled with the corpuscles produced in the gland, and flowing through 

 the cortex into the medulla and vasa efferentia, takes with it a part of the 

 cells formed in the cortical spaces ; and these cells are continually repro- 

 duced. This would appear to be the more correct aecount, because we cannot 

 imagine that the whole mass of cells of the cortical alveoli moves onwards 

 with the same celerity as the entering chyle, for in that case the vasa 

 efferentia must contain far more cells than they actually do. From this 

 statement it will be seen, that I regard the contents of the alveoli as being 

 for the most part independent of the entering lymph for their formation ; 

 and if these contents are not stationary, yet at least they are not so varying 

 in their condition as the lymph in the afferent vessels : so that, even from 

 a physiological point of view, it appears wholly incorrect to consider the 

 lymphatic glands as being merely plexuses of lymphatic vessels. 



The lymphatic glands are subject to numerous degenerations. The most 

 frequent are effusions of blood into the alveoli, or pigmentary deposits as the 

 result of these, which may advance so far that the glands become reddish- 

 brown or even black, the bronchial glands especially. They are also subject 

 to thickening of their envelope and of the internal septa, to depositions of 

 fat in their blood-vessels, to hypertrophy with uniform increase of all then- 

 parts ; and lastly, they are the seat of tubercle and cancer. 



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