Alaria valida, チガイソ, エンドウコンブ, チヂミコンブおよびアラメの胞子のう群の発生が観察された. これらの胞子のう群はすべて葉体の形成表皮 から発生する. Alaria valida では, 形成表皮の二分によって作られた下位細胞から生じた突起が, そのまま遊走子のうに発生していく様式(L type)と, 下位細胞からの突起は遊走子のう細胞にならないで側糸となり, その後あらためて生じた2回目の突起が遊走子のう 細胞になる発生様式 (A type) との両者が観察され た. チガイソでは, A type または L type のみの場合と, この両型が混在する場合とがある. エンドウコンブでは, L type のみの個体と, A type に一部 L type が混在する個体がある. チヂミコンブお よびアラメは L type であるが, アラメの胞子のう 群が食害をうけ, その後に再生回復してきた胞子の う群は A type であった. 下位細胞からの突起は, 生殖器官である遊走子のうに発生するが, また側糸に発生していくこともあ る. それ故, 生殖器官の分化の決定は, 発生の最終 の段階でおこなわれる. また, A type の二次側糸 が発生する性質は, 非常に不安定なものである.
The process of spore formation on fruit-bodies of Coprinus macrorhizus f. microsporus developed by common-B matings, e.g., AB×αB, was examined, making use of a gene marker, f. The recessive gene f controls the formation of undeveloped fruit-bodies and links neither of the incompatibility factors, A and B. Monosporous mycelia from the fruit-bodies produced by the common-B matings, e.g., ABF×αBf, were analyzed for genetic constitution by pairing with two tester haplonts abf and Abf. Since, in most fruit-bodies, the progeny haplonts of the parental types, ABF and αBf, and those of the recombinant types, Abf and αBF, appeared in 1:1 ratio, it was presumed that karyogamy and meiosis precede regularly the formation of basidiospores with a few exceptions.
The flower buds of Trillium kamtschaticum, while undergoing meiotic late-prophase or metaphase I, were immersed into tap-water either at 7-12°or 25°for 24, 48 and 72 hours. In the present experiment the whole body of the plant was completely immersed after anthers were laid as bare as possible without removal of sepals and petals. Cytological fixations of PMCs were made at the ends of the treatment and 24 hours intervals thereafter. The results showed that (1) under the treatment of water-immersion at both 7-12° and 25°the meiotic division did not proceed, accompanying a phenomenon of coalescence of chromosomes; (2) after the treatment the 1st meiotic division proceeded more slowly than that of control. Further, it is also evident that the treatment of water-immersion effected (3) no induction of chromosome breakage and (4) at 25°increase of the aberrations in telophase I which were due to abnormalities of spindle function compared with those in control.
1. The observations of the chromosome numbers and the karyotypes were carried out on five species, one variety of Pertya and Ainsliaea. 2. The taxonomic position of A. uniflora was considered karyotypically. 3. The basic chromosome numbers were found to be 13 and 14 in Pertya, 13 in Ainsliaea. 4. A karyological similarity was found between A. cordifolia and A. fragrans var. integrifolia. 5. All the members of the genus Pertya, excepting P. scandens and P. glabrescens have peculiar karyotypes which can be called Macroclinidium type. 6. There are some differences between the characteristics of the karyotype of Pertya and Ainsliaea.