Intergeneric Hybridization in Cichorieae, VII

Abstract

1) Somatic chromosomes and meiotic divisions of 97 F4 individualsn of Paraixeris denticulctta and Crepidiastrum platyphylluin, were examined.2) In many individuals the somatic chromosome number was 10.. Only three had 11 chromosomes. In the root-tips of four individuals polyploid cells were observed besides the diploid ones. In some individuals. new types of chromosomes were observed.3) In the meiotic division some individuals had bivalents only. But in the others multivalents or prematurely separating bivalents were observed in abundance. The forms of the multivalents and the component chromosomes of them were quite variable even in one individual. More multivalents were observed in the earlier diakinesis than in the metaphase.The writer wishes to record his cordial thanks to Prof. SINOTO of the Tokyo Imperial University under whose direction the work has been carried out. Thanks are also due to Prof. OHUYE of the Matuyamakotogakko who afforded him much facilities during the progress of the work. The expense was partly defrayed from the Japan Society for the Promotion of Scientific Research to which the writer wishes to express his gratitude.