Abstract
Gall development of Schlechtendalia chinensis on Rhus javanica and emergence of alatae from galls were studied at Kyoto. The gall was formed in mid May to early June and slit open in mid October to early November. The maximum length, width and height of three galls marked were measured weekly during the period from gall formation to opening. An index of the gall surface area, which was calculated from these length data, increased exponentially till early September (when the host plant flowered) and then did with decreasing rates of increase till the end of September. After the beginning of October the gall stopped developing. Fundatrices (the first generation within the gall) began to larviposit in late June and the second generation in late July. The alatiform final generation arrived at the third larval instar in mid September. It seems that one apteriform generation can develop during August. Consequently, I conclude that there were at least four generations within the gall. Fifteen galls examined in October contained 1, 343 to 8, 438 alatae (including alatiform larvae). From two galls observed alatae emerged for 11 and 13 days, and the emergence was found between 9:00 and 17:00 usually with maximum numbers between 12:00 and 13:00.
