200 ‘ BOTANICAL GAZETTE [MARCH 
Rosen (8) considered the formation of the spireme as due to 
the fusion of chromatic granules, but failed to get a polar view 
of the thread showing its quadripartite structure. 
Némec (9) states that when the chromosomes have arrived 
at the poles, the chromatin coils send out pseudopodia-like con- 
tinuations which bind opposite sides net-fashion. The chromatic 
substance gathers next on the periphery of the chromosomes, 
and dissolves into granules which wander into the pseudopodium- 
like continuations. In regard to the cell division of Solanum, 
Némec states that at the time when the spindle surrounding the 
nucleus is finished, the nuclear membrane vanishes and varicosi- 
ties are to be seen in the chromatic threads. He thinks that the 
longitudinal splitting must occur at this time, as he found in 
thin sections of chromatin pieces in pairs extending into the 
periplast. 
Hof (11) has a brief reference to what is doubtless the same 
condition which I have described in Allium. In stages of the 
dispireme, where the daughter nuclei are found, signs of a longi- 
tudinal splitting are rarely to be seen in the threads. The 
daughter nuclei present a structure similar to that shown by the 
nuclei of the prophase, except that they do not yet show the 
beginning of the enlargement of the nucleus. He thinks that 
very likely, owing to the quick succession of divisions in the cells 
of the meristematic tissue, those cells in which the longitudinal 
splitting is to be seen in the dispireme stage are to be considered 
as preparing for the ensuing division without the intervention of 
a resting stage. He does not hold this splitting to be a charac- 
teristic feature of the anaphase, as I do. Hof figures but two 
cells with signs of longitudinal splitting in the anaphase. 
The fact that after this apparent longitudinal splitting has 
occurred in the chromosomes of the dispireme all stages can be 
found showing gradual reduction in size of the chromatin bodies 
and increase of the linin, is evidence that this is not a temporary 
phenomenon. A criterion for removal of all doubt that these 
stages in the late anaphase may have been mistaken for those 
of the early prophase is the presence of the incomplete cell 
plate. 
