ORIGIN OF THE LYMPH CORPUSCLES. 343 



quently by F. A. Hoffmann, under my direction, in regard to 

 the genesis of the pus corpuscles, are of great importance, 

 since the characters of the latter agree in all respects with the 

 lymph corpuscles, migrating connective tissue corpuscles, and 

 colourless blood corpuscles. Insoluble colouring matters are, it 

 is well known, rapidly absorbed by all these contractile cells 

 when brought into contact with them. If, now, some such 

 colouring matter, capable of being easily recognised (for which 

 purpose vermilion is best adapted), be introduced into the 

 bloodvessels of a living animal, the colourless corpuscles take 

 up the particles into their interior ; if, at the same time, an 

 inflammatory process be excited in some organ, as in the 

 cornea, pus corpuscles containing this colouring matter may 

 be met with in the inflamed connective tissue, and even in the 

 healthy cornea, but it is especially in the loose interstitial con- 

 nective tissue that some migrating corpuscles containing the 

 pigment may be discovered. We can only draw the conclusion 

 from this, that such corpuscles must have been sufficiently ap- 

 proximated to the circulating blood to be able to withdraw the 

 pigment from the blood. The simplest view is that they have 

 entered in the blood itself, and thus, previous to their migration 

 into the tissues, were colourless blood corpuscles. On this ground 

 Cohnheim is opposed to the theory of Yirchow, according to 

 which the pus corpuscles originate in the connective tissue 

 itself, and maintains that pus corpuscles are nothing but 

 vagrant colourless corpuscles, and consequently are formed in 

 those organs to which we refer the origin of the latter ; that is 

 to say, in the spleen and lymphatic glands. The immediate 

 consequence of this doctrine is that the healthy migrating con- 

 nective tissue corpuscles, as well as the lymph corpuscles of the 

 peripheric lymphatics, must be brought to the tissues with the 

 blood, and that both originate in the spleen and lymphatic 

 glands ; the latter, however, in the circuit of the blood through 

 them, would certainly furnish similar cells to those which are 

 brought to them in the vasa afferentia, which would also pass 

 out by the vasa efferentia. There are still some additional 

 grounds of support to be adduced for this doctrine of the mi- 

 gration of the colourless blood corpuscles. Cohnheim in par- 

 ticular rests upon direct observation of the first stages of 



