The diploid number of chromosomes in the male plant is 17 and in the female 16.
Of the 17 chromosomes in the male, 14 are autosomes and the remaining 3 sex-chromosomes. The sex-chromosomes are almost equal in size and they are larger than the largest autosomes.
There are two V-shaped large X-chromosomes in the somatic division of the female plant, while only one such chromosome beside 2 large J-shaped ones (Y₁ and Y₂) can be found in the male.
The sex chromosomes form a tripartite complex in the reduction division of the pollen mother cell. The X-element in the middle of the tripartite chromosome goes to one pole and the Y₁ and Y₂ attached to both ends of the X pass to the other.
The sex-chromosome complex is not a simple XY pair as first described by WINGE (1923). Such a figure (Fig. 3), from which WINGE drew his conclusion, is only a transitory form to the V-shape arrangement (cf. KIHARA 1927. P. 442). The behavior of the tripartite sex-chromosomes in Humulus japonicus is, therefore, quite identical iwthht atof corresponding stages in Rumex acetcsa.
WINGE'S figures (Fig. 11 and 12) representing diakinesis of a pollen mother cell and 16 chromosomes of an archespore mother cell are quite in accordance with my observations.
The chromosomal formulæ of the plant are as follows:
diploid haploid
_??_ 14+Y₁+X+Y₂ 7+X, 7+Y₁+Y₂
_??_ 14+X+X
The diploid number of chromosomes in Humulus lupulus (_??_) is 20.

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A series of crossing experiments were made with certain varieties of the soy bean, concerning specially the chloroplast colorations of (1) the cotyledons in seed grains, (2) the cotyledons born on seedlings, and (3) seed-coats.

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[in Japanese]

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A vegetative mutation occurred in a seedling of Petunia violacea bearing otherwise normally green leaves, giving rise to a variegated sectant (see the photograph on the page 86). The seedling, registered as Pt. 261, was divided on this account into three parts, i.e., (1) G-sectant with green leave, (2) V-sectant with white-margined leaves, and (3) W-sectaut with white leaves. The white leaf lacks green chloroplasts entirely, and the white-margined one proves itself to be a whit-over-green periclinal chimera lacking green chloroplasts in the epidermis and some sub-epidermal cell-layers. In crossing each sectant with a normally green plant, resistered as Pt. 45, reciprocally (see the table on the page 87), it was witnessed that the chloroplast deficiency under cosideration is inherited through ovules only but not through pollen, and that the progeny of the crosses concerned is either normally green or albino. It is likely, therefore, that one deals in the present case with a variegation belonging to the category II, A, b in Winge's classification of variegation (1919).

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