Studios on the Cytology of some Spccies of Taraxacum. 
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I. Field-Experiment. 
The castration was carried on from the middle of March to the end 
of April 1912, both in T. albidum and T. platycarpum. The former, 
which is less common near Komaba, has white flowers and is charac- 
terized by having much larger leaves, flowers, flower-stalks, fruits, etc. 
than the latter. T. platycarpum is very common in Komaba and has 
yellow flowers. 
Several dozens of the flower-hcads of T. platycarpum were enclosed 
in the bags of parchment-paper before the opening of the flower to hinder 
the cross-pollination as in Ikeno’s experiment and my results confirmed 
entirely his experiments, for no seeds were obtained by such treatment. 
The castration-experiment was also carried on in the same species, but 
the resnlt was, of eourse, entirely negative. 
Many flower-heads of T. albidum were treated very carefully in 
the same manner and I found tliat almost all flower-heads, enclosed in 
the bags of parchment-paper, have produced great many normal seeds; 
moreover it was found that several castrated flower-heads produced 
seeds as normally, though many of such heads have withered away and 
fallen to the ground. Tliis early withering of the flower-heads is without 
doubt due to the severe injury caused by the razor during castration, 
though tliis was carried on with utmost possible precaution. We cannot 
be too careful about the period of castration, because the loculi of the 
anther easily split and allow pollen-grains to go out, even when flower- 
buds remain vet tightly closed. The castration at a too early stage, 
however, appears to be very injurious to the flowers and lead to tlieir 
withering. 
At any rate, my field-experiment leads me to the conclusion, that 
the normal fertilization is absolutely necessary for the production of 
seeds in T. platycarpum, while in T. albidum good seeds may be pro- 
duced parthenogenetically, as Ikeno has already thought probable on 
account of his experiment. 
II. Cytological Studies. 
The cytological studies upon tliese two species of Taraxacum, espe- 
cially, T. albidum are yet somewhat incomplete, owing to lack of sufficient 
material. But I think that the results obtained are of sufficient interest 
to be published already now. 
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