no EISEN. [Vol. XVII. 



stage. Darkly stained bars indicate the new chromosomes in the confluent mass, 

 all pointing in the direction of the cell axis. The spindle shows several con- 

 tractile fibers ending on the cytoplasmic membrane which has receded from the 

 chromosomes. On this membrane are seen several accessory archosomes, from 

 some of which radiate fibers. From one of these archosomes proceed the 

 remains of retractile fiber cones. The reddish blotches are the remains of the 

 plasmosphere. Some of the accessory archosomes are furnished with distinct 

 centrospheres. In the chromosomes are seen a few endochromatic granules, 

 characteristic of the chromoplasts. The cell wall is made up of cytoplasmic 

 granules. 



Fig. 63. Spermatocyte, in the chrysanthemum stage, having entered the pro- 

 phase in which the individual chromosomes are being reconstituted. Only a 

 small section of the nucleus is seen. Only one cell is figured. The cytoplasmic 

 or false membrane has been pulled back in order to allow the growth of the 

 nucleus. The central spindle is fully retracted and the archosome has assumed 

 its position at the apex of the fibers. Several accessory archosomes pulling fiber 

 cones towards the cell wall. Numerous accessory archosomes attached to cone 

 fibers, others are seen on the cytoplasmic membrane. Many of the accessory 

 archosomes are seen to have a centrosphere. 



Fig. 64. Spermatocyte. Spindle bridge ; remains of the central spindle which 

 has greatly contracted, many of its fibers showing muscular beading. One of the 

 dark granules is probably the archosome, it being situated where the granosphere 

 is being reconstituted. The cells which were connected by this bridge were in 

 about the same stage as the cell figured at 63. 



Fig. 65. Spermatocyte in the chrysanthemum stage, more advanced than Figs. 

 63 and 64. The chromomeres and chromosomes are plainly indicated and partly 

 individualized. The section passed obliquely to the central spindle, sho-wing 

 the cytoplasmic or false nuclear membrane with three or more accessory archo- 

 somes, from which radiate several fiber cones. This is not a free cell, but one 

 which was connected with another cell by a spindle bridge. 



Fig. 66. Spermatocyte in the chrysanthemum stage. The ceUs are not yet 

 separated, but connected by a cell wall and a spindle bridge. Several fiber cones 

 are formed on the cytoplasmic membrane, pulling the latter away from the 

 nucleus. The accessory archosomes are not as distinctly stained as in the other 

 cells, which is due to the greater washing out of the iron stain. A mid-body in 

 the center of the spindle bridge. The retractile fibers are emanating from the 

 apex of the upper spindle pole. 



Fig. 67. Spermatocyte in the chrysanthemum stage ; the cells are not yet sepa- 

 rated. The central spindle is greatly contracted, the fibers at each pole are being 

 retracted and condensed into a reconstituting granosphere. The fiber cones have 

 advanced towards the cell wall, the accessory archosomes actually resting on the 

 cell wall. Several paracellular bodies are seen on the cell wall, some being con- 

 nected with the cell by fine threads. Retractile fibers emanating from the poles 

 of the central spindle. The accessory archosomes at the poles of the fiber cones 

 are too much washed out to be distinct. From two to three fragments of the 

 plasmosphere in each cell, easily identified by their deeper stain. 



Fig. 68. Spermatocytes in the chrysanthemum stage. The two cells are more 

 separated than in the preceding figures. The fiber cones have reached the cell 

 wall, and some of them have receded from the cytoplasmic membrane. The 



