STRUCTURAL ELEMENTS OF THE CYTOPLASM. 19 1 



scattered and more independent of the limosphere or its remains. 

 The limosphere now begins to elongate, its staining capacity 

 (with hematoxylin or acid fuchsin) rapidly changes, and a 

 portion of its substance is gradually separated off and deposited 

 along the blepharoplast at the anterior end of the sperm (Figs. 

 17 and 1 8). The remnant of the limosphere (Fig. 18) takes no 

 further part in the development of the sperm, although it under- 

 goes further characteristic changes in morphology and staining 

 capacity. The part deposited at the sperm tip is the so-called 

 apical body. It begins very soon to elongate (Fig. 19), and by 

 means of acid fuchsin I have been able to follow its later history 

 and to show that it probably stretches out along the elongating 

 nucleus, forming thus a rod-like "acrosome" comparable to 

 that in some of the Pentatomidae. 



The interpretation of these phenomena seems fairly clear. 

 The relation of the osmiophilic platelets to the developing 

 limosphere suggests in every way the formation of the acrosomal 

 material in those animals in which the Golgi bodies do not fuse 

 to form a single, permanent mass the acroblast. The structure 

 of the limosphere is remarkably similar to that of many secretory 

 granules and of the acrosomal vesicle and granule of animal 

 sperms. The ultimate history of the apical body portion in the 

 moss sperm is again exactly comparable to that of the acrosome 

 in animals. The unexpected difference presented by the division 

 of the limosphere does not, so far as I know, ever occur in animals. 

 This unusual behavior together with the staining of the limo- 

 sphere at this period (Figs. 17 and 18) led to my erroneous 

 conclusion that the remnant of the limosphere was equivalent 

 to the Golgi remnant in animals. It is clear, however, that the 

 essential homologies which I first pointed out (Bowen, '266) 

 between the formation of the apical body and the osmiophilic 

 platelets still hold. My conclusion that the osmiophilic platelets 

 produce the acrosomal material in the moss sperm and that 

 they are therefore equivalent to the animal Golgi apparatus can, 

 therefore, now be reaffirmed. All the evidence available from 

 sources of every kind bears out my contention that the osmio- 

 philic platelets represent such part of the Golgi apparatus of 

 plant cells as can now be certainly identified. It would be extra- 



