Abstract
Lycosa T-insignita BOES. et STR. was reared under three different feeding conditions for invetigating the instar numbers and the carapace width growth. The number of instars necessary to maturity was variable with the feeding condition, i.e. it and its variation tended to be increased and much wider respectively as the interval of food supply was prolonged from the every day feeding to the fourth day feeding. Nymphal period was also extended by food supply at longer intervals. The growth curve of carapace width did not fit with that expected from DYAR'S law. The growth of carapace width was almost accomplished by moulting, and further a very small growth was found even within each instar, but not significant statistically. In comparison between adults which passed the same number of moults under different feeding conditions, the final carapace width in the individuals of every fourth day feeding was smaller than in those of every day feeding. From the frequency distribution, it was noticed that the carapace width measurement dit not give an accurate indicator for determining the instar of nymphs, excepting the first and the second instars. The carapace width distribution of field specimens was somehow similar to that of every fourth day feeding in the laboratory, suggesting poor feeding condition in the field.
