NYMPHALINAE: POLYGONIA FAUNUS. 355 



Food plants. The larva has been found on willow, Salix humilis 

 Mansliall, and black birch, Betula lenta L., belonging to neighboring 

 families ; and also upon currant (Fernald) and wild gooseberry (Caulfield, 

 Roberts ) , species of Ribes belonging to the very distant family of Grossu- 

 laceae. Mr. Edwards wrongly quotes Caulfield as finding it upon nettle. 

 I am inclined to believe that Betula is its favorite food-plant, having found 

 it thereon upon a dozen different occasions. 



Habits of the caterpillar. The caterpillar on emerging from the 

 egg devours only its crown, and then, although as stated the egg is always 

 laid on the upper surface of the leaf, crawls immediately to the under 

 surface where it spends the remainder of its days. Experimented on in a 

 closed box I found that it would keep to this surface of the leaf even 

 when the latter was reversed to bring it uppermost, so that the different 

 texture of the surface may have a special attraction for it, though an 

 instinct for concealment would seem to impel its action. So far as I have 

 seen it makes no nest of any sort in the open field, but may do so on 

 occasion, for in one instance in confinement, when about to change to the 

 last larval stage, it spun a feeble thread attaching three or four leaves and 

 drew them slightly together. During its early life it has a peculiar party- 

 colored or banded appearance produced by the alternation of dark and 

 light papillae. 



Life history. Although this butterfly flies the entire summer it is only 

 single-brooded. It hibernates as a butterfly and appears in the early 

 days of spring, but how early the data at hand do not enable us to say. 

 Gosse speaks of taking it at Compton, Canada, on April 15, and Bowles 

 says it comes out at Quebec at the end of May ; visits to the White 

 Mountains are usually not made early enough to speak positively, but it 

 must certainly be in flight there by the middle of May and probably much 

 earlier. In this same region it continues to fly in considerable numbers 

 until the end of June, may still be seen occasionally as late as the middle 

 of Jidy, and has been taken on the 18th. The eggs are laid here during 

 the latter half of May and the whole of June, apparently in a very 

 deliberate manner. These hatch in a week, the larva takes about five 

 weeks for its growth, and the chrysalis hangs from eight to fifteen days. 

 At the White Moantains fresh butterflies appear about the middle of July 

 before the old butterflies have disappeared. July 14 is the earliest date 

 noted. A caterpillar, the earliest ever found, brought to the neighborhood 

 of Boston, changed to chrysalis and gave the butterfly July 9, and in 

 Montreal, Mr. Caulfield raised some July 3 to 6 ; it is generally not until 

 toward the 20th or even later that they become common in Xew Hampshire, 

 but by the end of the month they swarm. Fresh individuals continue to 

 appear throughout the first half of August (or at least absolutely fresh 

 specimens may then be obtained), they generally continue abundant 



