THE BLOOD-PLATES. 



21 



out of small coagula, in a moist chamber, and move about in the 

 serum. Induction shocks cause them to withdraw their processes and 

 become spherical, and, if the shocks be not too severe, their movements 

 recommence. Strong shocks kill them. is necessary for their 

 movements. These amoeboid movements are of special interest on 

 account of the "wandering out" (diapedesis) of colourless blood- 

 corpuscles through the walls of the blood-vessels (Waller, Cohnheim). 



The chyle contains leucocytes, which are more resistant than those of the blood, 

 but less so than those of the coagulable transudations (Heyl). The leucocytes 

 of the lymphatic glands may also be dissolved (Rauscheubach). 



Relation to Anililie Pigments. Ehrlich has observed a remarkable relation 

 of the white corpuscles to acid (eosin, picric acid, aurantia), basic (dahlia, acetate 

 of rosanilin), or neutral (picrate of rosanilin) reactions. The smallest protoplasmic 

 granules of the cells have different chemical affinities for these pigments. Thus 

 Ehrlich distinguishes "eosinophile," "basophile," and " neutrophile " granules 

 within the cells. Eosinophile granules occur in the leucocytes of amphibia, and 

 in the marrow of their bones. Human leucocytes exhibit a neutrophile reaction, 

 except in the case of those corpuscles that have large ovoid nuclei : the former 

 are said to be the early stage of the latter. The eosinophile corpuscles are greatly 

 increased in leukosmia. The basophile granules occur chiefly in connective tissue- 

 corpuscles and in the neighbourhood of epithelium they are always greatly 

 increased where chronic inflammation occurs. 



III. Special attention has recently been directed to a third element 





Fig. 7. 



' ' Blood-plates " and their derivatives, partly after Bizzozero and Laker. 1, Red 

 blood-corpuscles on the flat. 2, From the side. 3, Unchanged blood-plates. 

 4, A lymph-corpuscle, surrounded with blood-plates. 5, Blood-plates 

 variously altered. G, A lymph-corpuscle with two heaps of fused blood- 

 plates and threads of fibrin. 7, Group of blood-plates fused or run together. 

 8, A similar small heap of partially dissolved blood-plates with fibrils of fibrin. 



