1891-92.] AMPHIBIA BLOOD STUDIES. 247 



the nuclear chromatin is arranged in the form of a network in every 

 respect like that in the nucleus of the red ceil. In such cases one 

 rarely finds the Indigo-carmine Fluid to react as it does in the nuclei 

 of the intact red cells, giving a light red stain to the interfilar chromatin 

 and a green or a blue-green color to network. These are evidently cells 

 which have had but a very short history as fusiform cells, that is, they 

 have been but recently formed, while the other elements which do not 

 show these peculiarities are more pathological by reason of their longer 

 existence as fusiform cells. 



4. The nuclei of these elements are admitted by Bizzozero, Hayem, 

 to present resemblances to those of the red cells. These observers, 

 however, took for study the blood of animals in which the red, white and 

 fusiform cells are comparatively small, and consequently were unable to 

 determine the more important points of resemblance. 



We can, therefore, on the view that the fusiform elements are the 

 remains of ruptured red cells, explain the absence of a membrane, the 

 capacity for adhering to each other, the similarity in shape, size, structure 

 and staining reactions between their nuclei and those of the red cells 

 when freshly ruptured. We can, moreover, explain their occurrence 

 thereby without referring in any way to the haematoblasts or to the 

 leucocytes, and we have also explained to a certain extent the fate of the 

 red cells — what was not done before. 



One can readily determine the fate of these fusiform corpuscles even 

 in cover-glass preparations of Necturus' blood fixed with osmic acid, 

 picric and especially corrosive sublimate. Fig. 22 a represents a fusiform 

 corpuscle in which there is a distinct and coarse chromatin network with 

 a certain amount of interfilar chromatin. At a later stage the trabeculae 

 of this network become thinner and finally disappear, and when this 

 happens the whole nucleus takes a uniform stain with various dyes. 

 Sometimes the nodal points of this network alone persist and may 

 appear as nucleoli. In the now homogeneous nucleus lobation may 

 ensue (Fig. 22 c, e. /.), and the lobation may go so far, accompanied by 

 a transformation of the shape into that of a more or less round mass, as 

 to render them extremely like leucocytes. They possess now no amoe- 

 boid properties whatever, and their cytoplasma, which is now compara- 

 tively abundant, begins to lose its eosinophilous character while the 

 nuclear chromatin reacts less readily and more feebly to dyes. As such 

 they are broken up, probably in the circulation and more especially in 

 the vessels of the spleen. 



As factors operating in the production of the fusiform cells, mechani- 



