The markings of the newly hatched larvae were studied from the physiological genetical point of view, using about forty mutants.
The color tone of the “A” marking (the Ist segment) becomes decreased and less distinct under the influence of the oily gene. The segments, which receive the effect of the E allelomorphic genes in the larval stage, appear more deeply black than other segments. The yellow substance (xanthopterin B) in lemon (lem) is already recognized at this period.
Histology of the “A” marking and the black or brown parts clarifies that, in these regions, the black or brown pigments are deposited in the nodules and the primary cuticle layer. The distribution of the nodules are regular and dense in these pigmented parts, but irregular and scattered in others (the 4th segment etc.).
Some experiments were made concerning melanosis as an approach to the analysis of the pigmentation. Melanosis is clearly demonstrated in the blastokinesis and just after hatching, except for the blushed eggs. As a substrate relation, tyrosine and phenylalanine are found abundantly in the eggs, but nearly disappeared on hatching (by means of the paper chromatography).
On examining with the spectrophotometer, the black and brown pigments mentioned here are identified as melanin.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract

1) The oxygen consumption and the respiratory quotient of the post-diapause silkworm eggs (Bombyx mori L.) during incubation (25°C) were determined by means of the WARBURG'S manometric method.
2) The oxygen consumption was very low at the beginning of the incubation, and steadily increased following the development of the embryo. After the “rotation” stage (6th day of incubation), particularly after the “eye-spot” stage (8th day of incubation) it increased rapidly (Fig. 1).
3) The respiratory quotient from the beginning to the end of incubation was 0.6-0.7 suggesting that the chief energy source was fat (Fig. 1).

View full abstract

[in Japanese]

View full abstract

The time from feeding of mulberry leaves until evaculation in the silkworm larva which is starved for a definite period becomes shorter than in the control. As the starvation period is longer within the limits of 20 hours, the time until evaculation becomes shorter but in the case of 24 hours starvation reverse phenomenon is observed. When starved for 16 hours or more longer, the leaves fed again appear in the first or the next excrements.

View full abstract

1) The separation of 2, 4-dinitrophenylhydrazones of aldehydes and ketones was studied by the paper partition chromatography on the filter paper impregnated with silicic acid, and this method was attended with good results.
2) Using this method for the investigation of the volatile carbonyl compounds in the mulberry-leaves, eight kinds of aldehydes and ketones were isolated.

View full abstract