1. The expressivity of curled character in Drosophila melanogaster is influenced by the environmental conditions. One of these is the nutritional condition through the larval stage: the better the nutritional condition the more typical the curled character. Another is the cultural temperature: the higher the temperature the higher the expressivity. The temperature-effective period is in the last day of the pupal stage. These properties of the curled phenotype are identical with those of Curly character, although the level of expressivity is far lower in the former.
2. When these two mimic genes are combined, the curling appearance of the flies changes increasingly; the recessive curled gene is incompletely dominant in the presence of the Curly gene.

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The lethal lemon and the lethal albino larvae1) show some phenotypical resemblance. In both, the lem and the al larvae, the mandibular cuticle does not develop properly, so that they cannot chew mulberry leaves and starve to death immediately after the first moulting. The lethal lemon larva contains in its epidermis a large amount of yellowish pigment which gives the body a yellowish color, while the lethal albino larva has a light brown color.
It has been confirmed in my previous experiments2), 3), 4) that +, lem and lem^l form a multi-allelic series. In order to investigate the genetical relation between the al and the lem^l genes, cross experiments between the two strains and between lemon strain (lem/lem) and albino strain were carried out. From the experimental results it was found that al gene does not locate on chromosome III. However, the linkage group to which al gene belongs has not yet been clarified, although linkage tests of al to several genes of the known other linkage groups were tried.
In another experiment5) it has been proved that the lethal lemon and lethal albino are different in their metabolic physiology. The gene lem^l is mainly responsible for abnormal pterin formation, while the gene al has a weaker capacity to form melanin. These physiological abnormalities have secondarily effects upon other metabolic processes such as abnormal formation of the cuticular layer of the hypodermis and produce somewhat similar expression.

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1. The karyotypes of six species and one variety can be represented as follows:
Nigella damascena K(2n)=12=4A₁^m+6^csA₂^m+2^tB^st
N. hispanica K(2n)=12=4A₁^m+6^csA₂^m+2B^st
Ranunculus acris var. nipponicus K(2n)=14=4A^m+2B^m+2C^st+2D^st+2E₁^st+2_tE₂^st
R. gramineus K(2n)=16=8A^m+2B^st+2C^st+4D^st
Anemone Tagawae K(2n)=14=12A^m+2^tB^st
A. sikokiana K(2n)=14=10A₁^m+2^tA₂^m+2^tB^st
Pulsatilla dahurica K(2n)=16=10A^m+2B₁^st+2^tB₂^st+2^tC^st
2. The basikaryotypes found in Anemone can be classified into two large groups, one of which consists of two small groups slightly differing from each other (Fig. 6, A, B; C). The A-basikaryotype in Fig. 6 is quite equal to the basikaryotype of Hepatica, while the C is slightly differed from that of Pulsatilla (Ibid. D).

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146種2変種の苔類の細胞学的研究の結果次のことが明かになつた.
(1) 苔類の4目にそれぞれ染色体数, 核型の特性が見られる.
(2) 苔類では, 1組の染色体中最大 (H) および最小 (h) の二つ, またはその何れか一つが特に明瞭な異常凝縮を示す異質染色体である. 核型比較の結果, 苔類の最大, 最小の異質染色体はそれぞれ相同なものと考えられる. これら両異質染色体の進化は苔類の系統と並行し, 下等な苔では異質染色質が認められないか, または僅かであるが, 高等なものではこれが多い.
(3) 苔類の性染色体は例外なく異質染色体の分化したものである. 或る種では H, 他では h が分化したものである. よつて苔類の性染色体には起源を異にする2系統がある.
(4) ケゼニゴケ (Dumortiera hirsuta) の種内倍数体 (n=9, 18, 27) の分布は, その生育地の地質と密接な関係がある. すなわち, 一倍体は単に石灰岩土壌上に, 二三倍体は石灰岩のみならず, それぞれ7および22種の他の岩石の土壌上にも生育する. したがつて, 染色体数の増加に伴い, より多くの異つた種類の岩石に生育する.

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