*: 
282 A CYTOLOGICAL INVESTIGATION OF SOME SPECIES 

Fig. 67. Fig. 68. 
Fig. 67. Abnormal „pollen-diad” of G. G. N. G. x 1750. 
Fig. 68. Abnormal „homotype-division” of G. G. N.G. x 1750. 
any nuclear substance is present, they contain but very few chromoso- 
mes. The sixth cell, on the contrary, contains more than 70 chromoso- 
mes, lying in one plane, so that this cell probably divides once. Evi- 
dently the distribution of the chromosomes must have taken place in a 
very unequal way during the first division over the two daughtercells, 
one getting nearly all of them. 

Fig. 69. Fig. 70. 
Fig. 69. Formation of an abnormal „tetrad” of G. G. N. G. x 1750. 
Fig. 70. Hexad of G. G. N. G. x 1750. 
In fig. 70 a hexad is figured the cells of which are of very unequal 
size. This very irregular division of the pollen-mothercells leads to the 
most curious abnormalities. No rule is discernable. As fig. 69 clearly 
shows, there is no longer any fixed relation between the quantity of 
nuclear substance and that of the cytoplasm of the cells. Doubtless 
se peti, 
