The present study has been carried out on the epidermal pigments of silkworm larvae, especially on the red pigments which are present at the eye spots of normal and other strains or at the supra-spiracular lines, and the basement parts of abdominal legs of “Zebra”(Ze), “black”(pT) etc., and also on the purplish brown pigments contained in the epidermis of the crescent portions of “knobbed” larva (K), and the red pigments of “quail”(q) by which the silkworm looks reddish especially in the 5th instar.
1) By the paper chromatographic analyses using formic acid as the solvent for the above mentioned pigments extracted by acid methanol, all the red pigments of +p, Ze, p^Tand q exhibit an orange spot with Rf 0.82, whereas in the purplish brown pigment in the epidermel cells of the crescent portion of K, two different spots re seen beside the orange spot (Rf 0.82), i.e., red (Rf 0.76) and purple (Rf 0.50)(Fig.1). Thus it may be concluded that the red pigment has only one pigment component, and the purplish brown pigments have three components.
2) These pigment components eluted with formic acid are analysed by spectrophotometer. The orange component has an absorption maximum at about 450 mμ, the red and the purple have a sholder at about 480 mμ, and 520 mμ respectively (Fig. 2. and 3).
3) The chemical natures of these pigment components are as follows: by oxidation with H₂O₂ the orange colour changes to yellow and by reduction with Na²S₂O₄ turns pink. The red and purple pigment components become colourless by adding H₂O₂, but do not turn by Na₂S₂O₄ (Table 1).
4) These results support the following facts that the red pigments of the above mentioned strains are the same as or closely similar to the +chrome-I, and each red and purple pigment component in purplish brown pigments is plausibly homologous to + chrome-II and +chrome-III respectively, which have been distinguished in the egg and eye pigments of the silkworm (+chrome-I, II and la are tryptophan derivatives). From these results the author is inclined to regard these pigments found in the epidermal cells as the pigments derived from tryptophan.

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Fluctuation of the free sugars in the bark and the wood of the shoot of the mulberry tree “Ichinose” in Tokyo district, cut during the period from August to April, was investigated emproying the paper chromatography.
Stachyose and raffinose appeared during the period from October to November and disappeared from March to April. This tendency is the same as the preceeding report. Sucrose was found throughout the year, showing much increase in the contents during both the period from August to September and from March to April, and much decrease from October to November. On the contrary, fluctose was diminished during August and increased much during September and disappeared during the period from March to April prior to stachyose and raffinose. Glucose was found throuhghout the year showing slight decrease in the wood part during the period from August to September.
In November, many spots on the paper chromatography, corresponding to such sugars as maltose, arabinose, xylose and two or three unknown sugars in addition to those mentioned above were revealed. From these facts, it is considered that November is the time of the physiological turning-point in the mulberry tree.
Fluctuations of these sugars occured earlier in the wood than in the bark, and the change of their contents was more remarkable also in the wood than in the bark, showing much decrease especially in summer.

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It has been reported that temperature shock added in early larval stage of Bombyx causes a decrease in moulting-numbers. The author, however, found that Shoko-abura, one of varieties of Bombyx and four-molter is a special one at this point.
Larvae of the variety which were 12 or 24 hours old after the first feeding in each instar from the 1st till the 4th, were exposed to such a high temperature as about 34°C for the period from 12 to 48hrs. As a result of the experiment with larvae from the 1st to the 3rd, a large number of five-moulters appeared in both sexes, while no three-moulters appeared in any case.
In another experiment with the same method using other variety of four-molter, C-122, there appeared some three-moulters as expected from other's studies.
It may, therefore, be probable that Shoko-abura is a special one which is added an extra number to that of its own in moult by mean of high temperature shock given in the earlier stage of larva.

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From the results of the investigations on the staining features of the eggs laid by female moths of ω₁-1 mutant which has been injected with neutral red, nile blue and bismarck brown in several pupal ages, it has been ascertained that the hibernating eggs are stained dark, while the non-hibernating eggs are rather pale. The eggs of the polyvoltine races were also stained rather pale with those dyes, but they were paler than the nonhibernating eggs of the bivoltine. It is seemed that these differences are due to those in the permeability of the dyes into the ovary.
The moths which were injected with the dyes on 5 or 6 days after pupation could lay stained eggs. Those which were injected on 9 or 10 days after pupation laid eggs of two types, stained and unstained. The eggs which were laid early in the oviposition did not be stained with these, while those laid lately were stained. It was clearly observed in the dissected moth that the unstained eggs has already cast off the follicle cells. The experiment shows that the folicle cell of the ova gives the stainability to the colion, which is accelerated by the voltinic hormone secreted from the subesophageal ganglia.

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Nach den bisherigen Beobachtungen an vielen Arten der Insekten über die Keimblätterherkunft des Subösophagealkörpers sind drei verschiedene Ansichten vertreten: die Ansichten der entodermalen, dermesodermalen und der ektodermalen Herkunft. Ich untersuchte die Seidenraupe, Bombyx mori L., um zu bestimmen, welche dieser Meinungen richtig ist. Es bildet sich nämlich im Körper der Raupe allmählich ein Gewebe aus dem Mandibularmesoderm heraus, welches sich dem Stomodaeum entlang nach hinten schiebt und schliesslich als Subosophagealkörper dicht dem Mitteldarm anzuliegen kommt. So ist es nach meinen Betrachtungen klar, dass dieser Körper, ungeachtet der definitiven Lage am Mitteldarm, vom Mesoderm seinen Ursprung nimmt. Was die Auffassung der ektodermalen Entstehung betrifft, so ist mir die Möglichkeit kaum zu denken.

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For the purpose of rearing the wild silkwom, Quercus trees were cutted off at 1.5-1.8metres above the ground in early spring and many new shoots were regenerated from the remaining stocks. Leaves of the regenerated shoots on the cutted stocks had deeper color, and were larger and thicker than those of the shoots on the uncutted control trees.
It was found that the content of water and that of protein per dry matter were far greater in the former leaves than in the latter, while the contents of such substances as carbohydrates, crude fiber, other extracts and crude ash per dry matter were somewhat smaller in the former lerves than in the latter ones.
The wild silkworms were reared in both Quercus forests of the cutted trees and those of the uncutted trees. The silkworm which feeded on the leaves of the cutted trees showed the following results in comparison with those which feeded on the leaves of the control trees:-smaller persentage of dieased worms, greater percentage of sound pupae, smaller water content of larvae, larger refractive indices of body fluid of larvae, shorter duration of larval stage until maturation and more uniform growth of worms, and heavier weight per cocoon, cocoon shell and pupa.
Summarizing the experimetal results mentioned above, it was concluded that the regenerative growth induced by stern-cutting of Quercus trees brings about those changes of leaf qualities as compared with the leaves of control trees which result in improvement of the feeding value of the leaves for rearing wild silkworms.

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An experiment was performed concerning the relation between the amount of ammonia evolved from cocoon shell by heating and that of soluble nitrogen from it in boiling water. The results obtained were as follows:(a) The amount evolved increases in proportion to the rise of temperature.(b) The amount of soluble nitrogen decreases in inverse proportion to that of ammonia evolved.(c) Provided the humidity at the time of heating increases, the amount of ammonia and that of soluble nitrogen decreases in liner. The rate of decrease in both elements is proportional.

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