1. Experiments were carried out on the effects of the flooding or drying the soil on the assimilation as well as the growth of the top and root of the mulberry tree grown inthe Wagner's pot, during the period from July to August in 1951.
2. When the soil was flooded, the growth of root stopped at once, while the growthof top decreased gradually and stopped at last. When the flooded water was driven out afterthe growth of the top stopped, the growth of the root resumed after 3 days and the rateof growth attained the 'same level as the control plant after 4 days. The growth of thetop did not recover after 5 days.
3. When the pot planted with mulberry tree was left without irrigation, the growthof the top and root of the plant decreased gradually until it stopped. If irrigated at thistime, the root began its growth after 2 days and reached the same rate of growth as thecontrol after 3 days, but the growth of the top did not recover after 5 days.
4. Both in the flooded and dryed plant the rate of assimilation was found to decrease.In the plant which was left without irrigation, the growth and consumption got equilibriumat the time when wilting began, after that period consumption surpassed the assimilation.
5. When the plant was irrigated when it began wilting, the absorption of water recoveredat once, and the water content of leaves increased. The assimilation, however, seemed to recover 2 or 3 days later than it.

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1. In Matsumoto district (a central part of Japan) the time of emergence of moths of Anthereaea yamai Guerin extends over 3 months from July to October, and is very discontinuousand irregular. This is considerably troublesome as well as uneconomical toobtain eggs for practical purpose. So an exprimental study was undertaken in order toshorten the period of emergence by means of treating the pupae with low temperatureswith the following results.
2. In 1953, when the pupae were exposed to natural out-door temperatures duringthe whole period, they transformed into adults within 63-65 days. This was completely thesame with those trated with a high temperature of 25°C for 25 days in the early period.But when the pupae were similarly in contact with a refrigirator temperature of 10°C, theperiod of emergence did last no longer than 30 days.
3. The date of the largest emergence was earlier by about 15 days in the pupae earlywith 10°C than in control pupae as well as those exposed early in 25°C. The number ofmoths appeared was also greater in the former as compared with the latters.
4. When the pupae were given with the low temperature in their middle stage, anyacceleration was not seen in the imaginal differentiation.

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1. It was found experimentally that the process of the imaginal differentiation of the pupae of Antheraea yamamai, Guerin is markedly retarded by the action of light.
2. When the pupae are placed in day-light and night-dark, day-dark and night-light, and continuously dark conditions, the period of emergence of the moths does not extendsover 49-60 days in all cases whereas, under the condition lighted with a 110 lux lump, theperiod covers so long period as 143 days with the pupae enclosed within cocoon from whichthe plant leaves are removed, as well as 108 days with them of untreated cocoons.
3. Even if the pupae whose emergence delayed by the action of constant light aretransfered into the continuous darkness, the imaginal differentiation or the emergence ofmoths takes place more rapidly than that of the pupae placed all the time under the lightedcondition.

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1) The body fluid of a new mutant silkworm “Aka-aka” was found to turn red instead of brack which is usually seen in the normal strains when exposed in the air.
2) A large amount of 3-hydroxykynurenine was found to be contained in this mutant body fluid times (20 times as much as those of the normal types) and its amount decreased as the body fluid turned red. Therefore, it is suggested that 3-hydroxykynurenine is responsible for the red coloration of body fluid.
3) To verify this assumption, the following experiments were carried out in vitro:
after exposure in the air
body fluid of the normal type blackish brown
body fluid of the normal type+ OH-kynurenine brown
body fluid of Aka-aka red
extract from normal body fluid+potato tyrosinase blackish brown
extract from normal body fluid++ OH-kynu. +potato tyrosinase reddish brown
extract from Aka-aka body fluid+potato tyrosinase red
(OH-kynurenine DL-3-hydroxykynurenine)
and it was assumed that both metabolites of tyrosine and tryptophan might be concerned together to the red coloration of the body fluid in this insect and that, in this case, both kinds of chromogens, derived from the different origins, might condense with each other.

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On the surface structure of a silk fibre there can be found visually or micro-scopically perceptible unevennesses, and besides electromicroscopic unevennesses and suchpure clean surface as atoms or molecules are thought to be combined with each other.
It is thought that all the unevennesses and the surface mentioned above act uponfriction at the same time. In this experiment, it seems that electromicroscopic unevennesses, above all, act remarkably upon friction.
The coefficient of friction is remarkably decreased with the increase of normalpressure and on the whole the equation U= aR-ⁿ is recognized to exist between theformer and the latter.

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A simple, handy, improved form of micro glass electrode, the membrane of which is in the shape of a spoon, requiring only 0.02-0.05 cc of liquid for examination aredescribed (cf. Fig. 1).
By this electrode it is possible to experiment with a quantity of the blood from oneindividual of 4th or 5th instar silkworm (Bonzbyx mori L.) and a pH determinationon the blood of silkworm takes only about a half minute (the blood can be poured intothe spoon directly from opening of the wound), the pH indicating the same valueduring this time without covering the sample with liquid paraffin etc.
This form of electrode has been employed for some 3000 determinations of the pHof blood of sillworms. A few examples are shown in Table 1.
This form of electrode is applicable to all sorts of liquids and especially convenientfor biological purposes.

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[in Japanese]

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OKAMOTO, one of the authors, investigated the amino acid contents in the crystalline and non-crystalline regions separated by means of the diluted HCI hydrolysis method, and concludedthat there could not been observed the differences in contents of both regions. Whiletwo components of silk fibroin were reported recently by COLEMAN, DRUCKER and AKABORI etal successively. But the relation between the two regions and the two components is complicatedand not clear, so that the authors tried to clarify this complicated relations and gotthe following results.
Silk fibroin of domesticated silkworm (Bombyx mori) and wild silkworm (Antheraea pernyiand A. yamamai) was dissolved in strong hydrochloric acid or in 85% phosphoric acid, andthen regenerated by neutralization, and these processes were repeated several times. Atevery process the regenerated fibroin was gathered and hydrolysed completely with 6 N HCI, and the hydrolysates were concentrated and devoted to the paper chromatographic method, and amino acids varieties composing of each fractions were detected and compared eachother.
In all cases the amino acids varieties of both fractions, corresponding to the regenerateand non-regenerate components, were fairly different.(Fig. I, Ia, II) MURASE reported that the crystalline region of the wild silkworm separated by means ofthe diluted HCI hydrolysis method was composed of such small molecular amino acid asglycine, alanine and serine. But we could not separate from the wild silk such region asabove mentioned with the same method.(Fig.III, IV)
Judging from the above mentioned facts, it might be concluded that the two componentsof fibroin are not the same with the two regions of it, and asumably the two or more componentsof fibroin intermingle in both regions and are not observed the distinct differences incomponents of both regions.

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[in Japanese]

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