THE CANADIAN ENTOMOLOGIST. 83 



THE LIFE HISTORIES OF TWO LYC^NID BUTTERFLIES. 



BY E. J. NEWCOMER, PALO ALTO, CAL. 



ChrysophaniiS zeros Bdv. 



Nothing has liilherto been written on the early stages of Chryso- 

 phanus zeroe, except a short description of the e^g, made from a single 

 specimen by Mr. K. R. Coolidge, in Psyche, XVI, 31. This egg was 

 collected by me at Deerpark, Placer Co., Cal, in 1908. It was the only 

 one found, and I did not at that time have ib.e leisure to hunt for others. 

 However, I spent six weeks in the same locality during the summer of 

 1909, and determined, if j)Ossib]e, to work out the life-history of this 

 species, which is quite abundant in the Sierra Nevada Mountains. The 

 one egg I had found (I saw the female lay it), was on an inconspicuous 

 plant not over eight or ten inches high, growing on a flat place among 

 other species of plants of the same general size and appearance. 



In 1909 I looked over the ground and decided that the food-plant of 

 zeros was one of two species. A careful search for eggs on these tvvo 

 species revealed none. I then watched every female I came across, and 

 one day was rewarded by seeing a female lay an egg, and it was on one of 

 the two likely plants. I immediately captured several females and con- 

 fined them under mosquito netting placed over growing plants of this 

 species, which is Polygonum douglasii Greene. The next morning all 

 that was left of the buttefflies was a wing or two — ants had taken care of 

 the rest ; but there were a number of eggs on the stems of the plant. By 

 a repetition of this method I secured about sixteen eggs. These eggs 

 were laid on July 27th and 28th. As they had not hatched when I 

 returned home, I put ihem in a cool place to hibernate. The larvae began 

 to come out on February 15th, and the last one hatched late in March. I 

 gave the first larvae leaves of our common Polygonum aviculare, but they 

 refused to eat them, and died in a few days. Several which hatched later, 

 I tried on Rumex^ and succeeded in rearing some of them. 



The young larva begins eating the shell of the egg at the micropyle, 

 and makes an irregul.u hole, through which it escapes. It does not con- 

 sume the remaining eggshell. The larva, in its earlier stages, eats pits 

 into the leaves, but in the last two instars the leaves are entirely devoured. 

 The larvae that I reared pupated about seven weeks after hatching, and 

 the adults emerged two or three weeks later. Thus in one case the larval 

 stage lasted 48 days and the pupal stage 17 days, making a total of 65 

 days from egg to adult. In another case the larval stage was 52 days and 

 the pupal 14 days, making 66 days altogether. 



March, 1911 



