iSgo.] NEW-YORK MICROSCOPICAL SOCIETY. 35 



the activities of the vegetable cell are manifested in its proto- 

 plasmic contents ; 2. Protoplasm consists chemically of a nitro- 

 genous basis ; 3. Protoplasm has no demonstrable structure ; 

 4. The protoplasmic contents in one vegetable cell are not con- 

 nected with the protoplasmic contents in adjoining cells ; 5. 

 The nucleus and other vitalized granules in the vegetable cell 

 are formed by differentiation from amorphous protoplasm ; " 

 and that, while the first proposition may be considered as finally 

 established, the conception of the second has been considerably 

 modified, and all the others have been completely disproved. 

 He says, further, that " instead of regarding the protoplasmic 

 basis as comparatively simple, it is now known to be exceedingly 

 complex, and to contain numerous cognate proteids, some of 

 which can be identified in the basic mass, others in the nucleus, 

 and others still in the vitalized granules ; " and that the results 

 of various studies "compel us to recognize in protoplasm a 

 substance of bewildering complexity of composition and 

 constitution." 



This fact began to be apparent in the animal realm when 

 Heitzmann, Klein and others announced the discovery of an 

 " intra-cellular net-work " in the white blood-corpuscle, the 

 points of intersection of the reticulum being what had been pre- 

 viously called the granules. In a paper read before our New York 

 Academy of Sciences in 1879,*° Doctor Elsberg called attention 

 to the communication to the Vienna Academy, in 1873, in which 

 Doctor Heitzmann " demonstrated the existence of a net-work in 

 amoebae, blood-corpuscles of astacus and of triton, human color- 

 less blood-corpuscles and colostrum corpuscles ; and, from 

 direct observation of the changes in the reticulum during the 

 contraction of the living, body, announced that the substance 

 constituting the net-work is itself the living matter or bio- 

 plasm ;" and Doctor Elsberg himself endeavored to demonstrate 

 a similar structure in the red blood-corpuscles. 



I can well remember, as perhaps you also can, the disgusted 

 incredulity with which this new doctrine was received, — an in- 

 credulity in which, I confess, I then shared I am not sure that 

 the appearance of a reticulum in the prepared blood-corpuscle 

 is even yet generally accepted as evidence of a normal structure 

 of the kind claimed by Doctor Heitzmann ; but the claim cer- 



20 ■• fhe Structure o' Colored Blood-Corpuscles." Armals N. Y. Acad. Set. Vol. I. 



