ORIGIN OF THE LYMPH CORPUSCLES. 341 



impart to the chyle its opacity and dense white appearance ; 

 lastly, there are red blood corpuscles. The lymph corpuscles 

 are now universally admitted to be identical in all their 

 characters with the colourless corpuscles of the blood. They 

 show in particular the same constantly varying form and 

 the same phenomena of contractility, as long as they are 

 living ; whilst they assume the spheroidal form, which was 

 formerly considered to be their natural shape, as soon as 

 they die. The manipulations that up to a recent period were 

 adopted for microscopical examination very easily kill them, 

 and thus a fatal effect is produced by evaporation, by the 

 addition of water, or of saline solutions containing more than 

 2 per cent, of salt. Even mechanical agencies, as the weight 

 of the covering glass, are sufficient to rapidly extinguish all 

 indications of life. Whilst the substance of the lymph cells 

 during life is highly refractile, and even possesses a peculiar 

 brilliancy, it becomes paler and dull after death ; coincidently 

 there appear small points (perhaps fat drops) in its interior, 

 and in their centre a nucleus which is usually strongly gra- 

 nular. The corpuscles of the lymph, like the colourless cor- 

 puscles of the blood, are not all exactly alike; thus there are some 

 which present a granular character, whilst others present the 

 form of very large cells with multiple nuclei, and others, again, 

 are very small, and were formerly not recognised as true cells, 

 but were described as free nuclei. Undoubtedly in the latter 

 by far the greatest part of the body is occupied by the nucleus, 

 so that this is often only invested by an extremely thin layer 

 of extraordinarily pale cell substance, which very easily under- 

 goes disintegration. Lastly, we also sometimes find in Mammals 

 and Amphibia large lymph corpuscles with brown granules in 

 their interior, thus constituting pigment cells. In the various 

 sections of the lymphatic vascular system the quantity of these 

 elements varies, and they especially differ in their number ac- 

 cording to whether the organs from which the lymph vessels 

 proceed are in a state of rest or activity. 



From whence now do these various morphological elements 

 flow ? Where is their place of origin ? Formerly it was believed 

 that they only originated in the lymph path, and the element- 

 ary granules were regarded as representing the very commence- 



