Studies on the Cytology of some Species of Taraxacum. 
By 
J. Osawa. 
(College of Agriculture, Imperial University, Tokyo.) 
With Plates XXXVII— XXXVIII. 
The well known experiment of Raunkiaer (1903) showed, that 
many Taraxacum- species may produce good seeds, even when flowers 
are castrated in early stage. Murbeck (1904) and Juel (1905), who 
also stndied tliem embryologieally and eytologieally, concluded that 
parthenogenesis may take place in all species of Taraxacum. 
On the other hand, Rosexberg (1909) stated, that the typical tetrad- 
division of the embryo-sac-mother-cell takes place in T. confertum and 
Dahlstedt (1907) has expressed the opinion, that the normal fertilization 
may perhaps be necessary for the seed-production in certain Taraxacum- 
species. Ikex'O (1910) has also made many experiments in T. pJaty- 
carpum Dahlst. and T. albiäum Dahlst. and in the forrner species he 
never obtained any seed, when he, by enclosing the flower-heads in the 
bag of parchment-paper, hindered the cross-pollination, while in the 
latter, by the sanre treatment, he gained many seeds as normallv. Thus 
he concluded, that “die parthenogenetische Entwicklung der Früchte 
ist also hier (T. albidum ) wahrscheinlich, wenn auch die Selbstbefruchtung 
oder die Befruchtung innerhalb des Köpfchens keineswegs ausgeschlossen 
wäre”; and he continued, “so kann man sicher den Schluß ziehen, daß 
bei T. platycarpum keine Parthenogenese vorliegt.” 
At the Suggestion of Prof. S. Ikexo I repeated the castration-ex- 
periment in the spring of 1912 and made some c-ytological studies to 
throw further light in this question. Materials were gathered in the 
Botanieal Garden of the Agricultural College of Komaba through Bis 
kindness. 
For fixation acetic alcohol, Carx'Oy’s fluid and Flemming’s solution 
are employed, and the sections are cut 5 — 15 u in thic-kness. 
