Egg SCP ( –47.2 ±1.0℃) of Red-spotted Apollo butterfly, Parnassius bremeri, was lower than larva(–35.0 ±0.9℃). The difference (12℃) between egg and larva was revealed by chorion through scanning electron microscope (COXEM EM-30, Korea). But considering of about 6 months’ pharate 1st instar in egg from June to November, function of egg seems not to be overwintering mechanism but rather estivation. In order to identify estivation function of chorion heat stress was carried out. Experiment was conducted on the 4 conditions such as high temperatures of 25, 35, 45 and 55 °C for 2 hour, then allowed them to recover at 25 °C for 1 hour. Total 65 samples 0f 31 eggs and 34 pharate 1st instar out of an egg were used and replicated 3 times. All pharate 1st instar in egg and pharate 1st instar out of egg survived at 25℃ and 35℃. In case of 45℃ survival rate of pharate 1st instar in an egg (91.6±3.5%) was significantly higher than those (37.8±9.4%) of pharate 1st instar out of an egg. All was dead at 55℃.

SCPs on larvae and eggs of red-spotted apollo butterfly, P. brimeri were measured according to the method of Kim and Kim (1977) with a thermocouple, BTM-4208SD (LT Lutron, Taipei, Taiwan), to detect the release of the latent heat of fusion as body water freezed. SCP of larvae during March goes below –27.4±1.7℃ and egg scp during November goes –47.2±1.0℃. In order to identify the reason of the difference(-17℃) between egg and larva we took photographed egg through scanning electron microscope (COXEM EM-30, Korea). Chorion of P. bremeri were 100.1㎛, Papilio machaon and Sericinus montela in same family was 10.8㎛, 5.5㎛ respectively. P. bremeri was 10 times, 20times thicker than another species within the same family .