284 PROTOPLASM 



which can be obtained so often, is always, upon more exact 

 investigation, to be referred to the granules which it usually 

 lodges in great abundance. Now, since we know that the 

 granules, also very numerous in Amoebae, do not pass into 

 the hyaline protoplasm of the pseudopodia, its feeble staining 

 powers are explained easily by this fact. This explanation 

 will, at any rate, hold good for the white blood corpuscles, 

 since granules are, in like manner, present in them in 

 abundance. An apparently very sharp limit between the 

 darkly stained reticular central protoplasm and the hyaline 

 protoplasm of the pseudopodia may, however, in addition to 

 being caused by this circumstance, be also an illusive 

 appearance due to the fact that the real origin of a pseudo- 

 podium which is creeping flat upon an underlying surface, 

 may be covered, to some extent, by a bulging out of the 

 more or less raised central portion of the corpuscle. This 

 frequently occurs in the case of Amoebae creeping upon a 

 flat surface. Under these circumstances a sharp boundary 

 between the substance of the pseudopodia and the central 

 protoplasm is then, of course, apparently visible, since 

 the origin of the pseudopodium cannot be plainly traced in 

 objects of such small size. 



I think, however, that it is scarcely necessary to discuss 

 these objections more in detail, but that it will be sufficient 

 to refer to the above described observations upon the sudden 

 conversion of the apparently homogeneous protoplasm of the 

 pseudopodia into reticular protoplasm, which the hypothesis 

 of Leydig and Schafer is altogether unable to explain, while 

 it is perfectly compatible with my view. As has been said, 

 I consider my view with regard to the homogeneous proto- 

 plasm to be the more probable for these reasons, which 

 were developed by me in 1890, without Schafer having paid 

 any heed to them. There is furthermore the additional 

 fact, to which I will again call attention here, that as evi- 

 dence against the Leydig and Schafer hypothesis, which of 

 necessity assumes the existence of a spongy framework, there 

 are, of course, all those arguments which have already been 

 enumerated above against the possible existence of such a 

 framework. Schafer expresses himself rather indefinitely 



