The photoperiodic conditions which promote the growth of newly hatched larvae in an artificial-dietrearing are investigated, and the following results obtained;
1) The newly hatched larvae feeding in light begin to discharge earlier than those feeding in dark do. In the early stage of feeding the curve of discharge number plotted against time elapsed has a higher peak and a shorter period in the case of feeding in light.
2) Feeding in light gives more discharges and heavier body weights of larvae irrespective of the composition of diet.
3) The spectral range of light effective to their growth lies about from 550 mμ to 590 mμ.
4) The photoperiodic conditions during incubation have some effects upon the growth of newly hatched larvae, though not so seriously as those during feeding do.
5) Feeding in light promotes the growth in a large majority of silkworm races, but in a very few ones it has no distinguishable effect on the growth, or oc-casionally hinders the growth.
6) More than 18 hours are necessary in order for feeding in light to have an effect on the growth of silkworms.
In conclusion we have observed that in a majority of silkworm races feeding in light accelates their growth. On the basis of this observation we insist that the hatching of silkworms by illumination is not accidental, or rather the illumination plays an important role in facilitating the growth of silkworms.

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This investigation was carried out to clarify the combined effects of light intensity and temperature on the flower coloration and the growth of carnation plants, using the cultivars, “Coral” and “Shocking Pink Sim.”
The dimensions of leaf, petal and corolla increased under high light intensity and under low temperature. The degree of decrease in stem diameter due to low light intensity was larger at higher temperature. The elongation of internodes was promoted by the lower light intensity and by the lower temperature. The angle between leaf and stem was influenced not by light intensity but by temperature.
As to the change of flower color with the fall of temperature, the lightness de-creased in both cultivars, whereas the redness increased in “Shocking Pink Sim” and decreased in “Coral.”
Anthocyanin content was markedly enhanced with the fall of temperature, and the effect of light intensity on anthocyanin formation was remarkable at low temperature as compared with high temperature. The covering of flower buds with aluminum foil did not affect anthocyanin formation.

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The nutritional condition for the 1st instar larvae of silkworm Bombyx mori was found to be critical for the regulation of the entire length of larval development. This regulation could also be achieved by some physical environmental factors experienced during the embryonic stage. The treatment of embryos with low temperature was effective in promoting the delayed larval development under the poor nutritional condition. The interrelationship between these chemical and physical environmental factors may suggest a compensatory mechanism to achieve the proper larval development in this insect.

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