none At 25 degree C, the pre-oviposition, oviposition and post-oviposition periods of B. instabilis Marsh. were 0.50, 28.33 and 1.40 days, respectively, in mated females. The daily number of eggs laid per female was 7.72 eggs, while the total number laid per female during its life span was 233.5 eggs. Females lived longer than males at the 3 tested temperatures, 15 degree , 20 degree and 25 degree C. At 25 degree C and 60% RH (relative humidity), the mean longevities of males under the trophic conditions, water or honey and in case of starvation were 7.11, 26.33 and 5.30 days, respectively. The respective figures for females were 7.30, 29.14 and 5.68 days. Mean longevity of females fed on the body fluids of the host reached 30.75 days. The female could paralyze 7.7 larvae daily but the number of parasitized larvae was only 4. Sex ratio among samples collected from the field was 1 male : 2 female female , while in the laboratory it was 1:4, Anagasta kuehniella Zell. larvae were not accepted by the female parasite, while Pectinophora gossypiella Saunders larvae were highly accepted. At 20 degree and 30 degree C, and 60% RH, the total developmental periods of B. instabilis (from egg to adult) were 19 and 9 days, respectively, when reared on Phthorimaea operculella. The respective figures were 20 and 10 days when reared on Pectinophora gossypiella.