The result of this study indicated that the effect of high temperature on ovarian growth and development was marked in the Japanese oak silkworm, Antheraea yamamai. Ovarian growth and development in the 3rd and 4th instar larvae increased with an increase of temperature ranging from 20℃ to 29℃,and slightly decreased at 32℃.Whilst it was significantly blocked in the 5th instar larvae at 29℃ and 32℃.As mature larvae or pupae were exposed to 32℃ since the beginning of cocooning or 1st day after pupation,ovar...