In the F3 generation of triploid hybrids from Avena barbata (n, 14) × strigosa (n=7), the author has found a diploid strain which always segregates green and albino seedlings in a 1 : 1 ratio and gives no homozygous greens. This strain is called “green-inconstant”. This green-inconstant is especially characterized by very early maturity as compared with normal diploids or A. strigosa. The genetic analysis has shown that the green-inconstant may have a genic formula al++/+Reλ.where al is a gene for albino, Re for early ripening and λ for zygotic mortality.
In the cross, green-inconstant × normal (A. strigosa) two types of F1 hybrids have been obtained, one being green heterozygotes (al++/+++) and the other early heterozygotes (+++/+Reλ) In the following generations, green heterozygotes give green and albino seedlings in either a 6 : 1 or 5 : 1 ratio. By selfing, on the other hand, early heterozygotes always segregate early and normal plants in a 1 : 1 ratio. Owing to the coupling of Re and λ, all of these early segregates are heterozygous, but there is rarely found homozygous earliness which is probably free from the lethal factor. In F₂., generation of early heterozygotes (1 : 1 type) a new strain has been found, in which the earliness is obviously controlled by the normal monogenic inheritance (3 : 1). And it is further confirmed that about one third of early segregates bred true for earliness. From these results, it can be seen that all cases, except the last one, exhibit remarkable deviation from expectation on the Mendelian basis.
By crossing experiments, a new fact has been discovered that pollens with different genic formula accomplish fertilization in different frequencies as given in Table 11. Assuming such certations of pollens the genetic data mentioned above are clearly understood.
The origin of green-inconstants and the different frequency of the occurrence of homozygous earliness in different genotypes are discussed on the hypothesis of the structural change of chromosomes.
In conclusion the writer wishes to express his hearty thanks to Prof. H. Kihara, by whose direction this work was made.

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The classification of genus Triticum into four groups was accomplished by Lilienfeld and Kihara (1934) from the stand point of genom-analysis (Table 1). The present author has found that there are some remarkable differences among the four groups of Triticumm and its allied genera as to the modes of flowering. The results of observations reported in this paper were obtained in the months of May and June of 1939 and 1940 in the experimental beds of the Laboratory of Genetics of Kyoto Imperial University.
Earliness or lateness of heading
Taking into account the standard errors, the average date of heading for the Dinkel group is the same as that for the Emmer group, and that of Einkorn group is the same as that of the Timopheevi group. The Dinkel and Emmer groups are earlier in heading than the Einkorn and Timopheevi groups. In a comparison of the days elapsing from heading to blooming, the Einkorn group takes a somewhat longer time than the remaining three groups. Both Haynaldia and Secale take a far longer time than the Einkorn group (Table 2 and 4). There exists no correlation between the number of days and the stem length or ear length (Table 5).
Whole length of anthers and mode of their dehiscence
The whole length of anthers is least in the Dinkel and Timopheevi groups while in the Emmer group, the Einkorn group, the Haynaldia and Secale it tends to increase. As to the Hordeum, the whole length in the diploid species (H. spontaneum) is greater than in the tetraploid species (H. murinum).
The mode of dehiscence of anthers is clearly distinguishable among the four groups of Triticum, Haynaldia, Secale, Aegilotricum, and Hordeum (Figs. 1-2). In the genus Triticum, the split part of the anther is shortest in the Emmer group showing a percentage of 28.36 (the proportion of the split part to the whole length). Although the value for the Einkorn group is near to that of the Emmer group, showing 31.73 per cent, yet the Einkorn group is evidently distinguishable from the Emmer group, as to the occurrence of separate splitting in the mid-portion of the anthers.
The Dinkel and the Timopheevi groups differ from the two groups mentioned above owing to the larger figures for the percentages i.e. 62.99 and 67.86 respectively. Among the related plants, 82.85 per cent of the Secale cereale is larger than in the case of any other group of Triticum, 98.18 per cent of Aegilotricum is greatest of all, while 12.06 per cent of the Haynaldia villosa is the least of all the species of related genera. In Hordeum, the percentage for the diploid species (H. spontaneum) is 21.47 and that for tetraploid. (H. murinum) 47.94 (Table 2 and 6 : Figs. 1-2).
Order of blooming
In three varieties of T. aegilopoides the blooming occurs first in the upper half of the spikelets of the head. In the T. monococcum vulgare the first blooming occurs in the middle half, slightly nearer the tip of the head, while in T. monococcum flavescens it occurs in the mid-section, somewhat nearer the base of the head. In the Emmer group three types are found : in T. dicoccoides spontaneonigrum the first blooming takes place in the upper half, in T. durum coerulescens in the middle third a little nearer the tip, and in T. persicum fuiliginosum about in the middle of the head, In the Dinkel group, the first blooming occurs in the middle third of T. vulgare erytibrospermum, and in two varieties of T. spelta in the upper third of the heads. In T. Timopheevi, the spikelets which bloom first are in the mid-section of the head. In Haynaldia villosa, the blooming begins near the tip of the head and proceeds downward regularly (Table 7).
Number of flowers blooming on successive days
The distribution of the number

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完熟した精子束がその種特有の囘旋をしてゐることを見出したので, 囘旋の方向, 囘數, 角度, 半徑及び長さ等により鱗翅目昆蟲を數型に分つことが出來ることを示した。囘旋は精子の完熟と同時に, 同じ要因によつて生するものであるととを推論し, 又囘旋状態より精子の蓮動の状態を論じ, 且つ異種間の人工交配を行ふ場合には前位腺液反應と共に囘旋歌態も類似した昆蟲を選ぶことが必要であらうと推論した。

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The chromosomes of the crayfish, Cambarus clarkii were investigated in spermatogenesis. This species was originally introduced from America. At present it abounds in the neighbourhood of Tokyo. The spermatogonial complex shows 192 chromosomes, of which 6 (3 pairs) are atelomitic V-shaped while the remaining are telomitic rod-shaped (Figs. 1-2). The haploid chromosome number, 96, was observed in the primary and secondary spermatocytes (Figs. 3-4 and 6). No evidence for the presence of the particular chromosomes could be found in the present species. The following table shows the numerical relationship of the chromosomes of the species belonging to the Potamobiidae so far studied.

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The present paper deals with the chromosomes observed in male germ cells of Euscyrtus karyni and E. formosanus belonging to the Podoscyrtinae of the family Gryllidae. No numerical and morphological differences of chromosomes were observed between these two species, as clearly seen by reference to the accompanying figures (Figs. 1-11) and the table given below. The only visible difference lies in the size of cell; Euscyrtus karyni is larger in its cell size than E. formosanu.

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