Abstract
Effect of various factors on the ovipositional behavior in Papilio demetrius CR. were examined and a factor(s) in the host-plants, which directly stimulates oviposition response, was explored.The "drumming" action of butterfly by the forelegs was indispensable for inducing the subsequent ovipositional behavior, and removal or manicure-coating of the foretarsi did completely prevent the oviposition response. In the female butterfly, characteristic brush-like trichoid sensilla were found on the ventral surface of the 5th tarsomere of foretarsi. The surface texture or color of the oviposition substrate had no relation to the oviposition response. Moisture per se also had no appreciable effect on eliciting oviposition, though it exhibited some effect with an oviposition stimulative factor(s) from the host-plants.Expressed juices from leaves of the Rutaceous host plants as well as from the epicarp of lemon elicited the normal oviposition response, but those from Rutaceous non-host plants had little or no effect. Although the steam distillate and extracts of leaves of the host plants with several organic solvents showed no activity on the oviposition, the water extract and the residual aqueous solutions were obviously effective. Several kinds of essential oils from the host plants and their authentic component chemicals had consistently to effect. The oviposition response of P. protenor seems to be caused not by these odorous components, but some contact-chemical factor(s).
