Fertilization in Finns Strobus . 459 
the entire breadth of the nucleus, and a slender bipolar spindle, 
such as is shown in Fig. 80 b . As the halves of each chromo- 
some separate at the point where the spindle fibres are 
attached, the longitudinal splitting of the segments becomes 
evident throughout the entire length of the chromosomes 
(Fig. 80 b). 
During mitosis, the deeply staining substance surrounding 
these nuclei condenses into large irregular masses. When 
the eight nuclei are formed, this deeply staining material 
collects about them and extends in irregular strands into the 
cytoplasm. Each nucleus is now surrounded by its own 
cytoplasm, though no cell-walls have yet been laid down 
(Figs. 79 b - 80 b). The deeply staining, cytoplasmic substance 
appears to be repelled from all sides of these nuclei and is 
deposited in lines which indicate the position of the future 
cell-walls ; the cell-membranes appear to arise by a direct 
transformation of this substance. The process seems to be 
very similar to that described by Farmer and Williams (’ 98 ) 
in Fuats. Mottier (’00) inclines to the view that the cell- 
plate is deposited in the form of a homogeneous fluid, the 
kinoplasm, even though its presence cannot be demonstrated, 
being the active agent in its deposition. The substance 
which is cast out, or passes out, from the region of the eight 
nuclei in the formation of cell-walls at the base of the 
oosphere in Pinus , has the appearance at times of a homo- 
geneous, deeply staining fluid, in which numerous irregular 
granules are embedded ; but there is never any evidence 
of its being purely fluid in nature. 
The origin and disappearance of the achromatic spindle 
in the several divisions, which have been followed within 
the oosphere of Pinus , indicate that, as in the division of the 
generative cell of the pines, so here, the spindle-fibres are not 
the expression of a special kinoplasmic substance. 
The so-called Proteid Vacuoles. 
The true nature of the proteid vacuoles is a subject which 
attracted my attention very early in the course of these investi- 
