Xenia which occurs in the endosperm is commonly found in maize, rice and other plants. But metaxenia is a curious phenomenon. This is caused by the direct action of pollen on the character of the fruit which consists of the ovarial tissues of the mother plant. SWINGLE and NIXON discovered this phenomenon in fruits of the date-plam and the former named it“metaxenia”.
We have observed a sort of metaxenia of Swingle or some such phenomenon in some plants of solanaceae.
The materials used in this experiment were the following three kinds of plants of genus Solanum.
S. citrullifouliun: The fruit is 7.8mm. in diameter on the average. It contains about 42 seeds, and turns red, becoming transparent when it matures
S. Delilei: The diameter of the fruit measures 6.7mm. on the average. Single fruit containing about 43 seeds becomes intransparently black-purple when mature.
S. aggregatum: The fruit is 14mm. in diameter on the average. It containes about 56 seeds, and becomes intransparently deep purple when it matures.
When the pistils of S. citrullifolium were pollinated with the pollen grains of S. Delilei, the fruits grew larger than those of the parents, containing no or very few filled seeds but many unfilled ones, and became, when matured, dark red colour, which was almost intermediate between that of their parents.
When the pistils of S. citrullifolium were pollinated with the pollen grains of S. aggregatum, the fruits became smaller than those of the parents and contained many uufilled seeds but no filled ones. The colour they assumed when ripe was intermediate of the fruits of their parents.
Xenia in the endosperm is easily explained by the double fertilization. But the explanation of metaxenia is still sought for. Swingle says that the embryo or endosperm or both of them secrete hormones, or some such substances, which biffuse out into the tissues of the ovary and affect them according to the particular male parent used to fecundate the embryo and endosperm. This is an interesting and clever explanation. In fact, the fruits grown by cross pollinating in our experiments were bluish in the center or near the seeds. As these fruits are observed through the red juice of the outer side, their colour seems intermediate one. Therefore it seems as though the seeds secrete some substances which change the colour of the fruit. But it must be added here that in all our cases the seeds in the fruits were nearly always unfilled or abortive ones. This fact makes the explanation difficult.
PH value of the juice of all kinds of these fruits were measured, but the results did not bring our cases to light.
Thus we shall reserve the discussion on this problem to still later work.

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In order to contribute a somewhat reliable basis to those of the previous studies of inheritance of face shape in swine, which have been chiefly made by means of observations of the face of living animals, the author measured directly the skull and the data are calculated.

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We have three races of sesame (Sesamum indicum, L.), classified in the colors of the seed coat. They are white sesame, black sesame and brown sesame, and they have each its peculiar characteristics.
Among the results of many experiments in the characters of these races a few of them will be mentioned here.
The stiffness of the seed coat of the black and the brown seeds is chiefly due to the thicknening of the lower part of the side wall in the epidermal cells with which a deposition of something like the crystals of calcium oxalate on the bottom wall is completely linked, and the tenderness of the white seeds is due to the contrary nature of the epidermal cells to the foregoing one. The behavior of the hereditary nature of this character follows a simple Mendelian rule, the stiffness being dominant over the tenderness and the heterozygotes segregating into “3 stiffs to 1 tender” in the F₂-generation.
The having colors on the seed coat is dominant over not having the same and the heterozygotes segregate in the F₂-generation into several colors of lower classes, but we have riot a plenty time to discuss the matter now.
The quantity of the chemical constituents of the seeds was analyzed by Dr. YOSHIMURA of the Kagoshima Imperial Colege of Agriculture and Forestry, and the results are as follows:
Water …… 8.570
Crude protein …… 22.088
Crude oily substance …… 44.560
Carbohydrates and Asbes etc. …… 24.782*
The analysis of my materials was performed by my colleague, Prof. KURAHASHI to whom I desire to express my hearty thanks, and the results are as follows:
The quantities of the crude protein and the crude oil in my analysis are nearly the same with those of Dr. Yoshimura's, and as in the last table those substances of the hybrids between the white (sometimes expressed in W.) and the black (sometimes expressed in B.) sesame, and its reciprocal one look like one of the cases of the maternal inheritance but in this case we must consider the structure of the seeds as to the generations to which the substances belong.
The seed coat is a part of the P-plant and the embryo as well as the endosperm are parts of the F₁-plant, and the proportions of the table are derived from the relative quantities of these two different generations. The appearance of the matroclinous nature in these substances can perhaps be accounted for in the relativity of the structure of the seed coat to the embryo and the endosperm; and if the quantities of these substances contained in the embryos only, be treated the hereditary behavior would have followed a simple Mendelian rule.

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