THE LEPIDOPTERIST 



93 



Some Notes on Basilarchia astyanax and var. 

 albofasciata Newc 



By Dr. Robert Unzickcr, Chicago, III. 



Uefore 1 describe my experience with the different 

 food plants of astyanax, 1 want to give a short de- 

 scription of the meihou by which I obtained the var. 

 albofasciata. 



During the last years 1 noticed that in Chicago's 

 surroundings albofasciata specimens were not very 

 rare. I never saw one in the spring; all were ob- 

 served in the fall, especially in August and Septerii- 

 ber. I thought that it might be possible to obtain 

 the variety in the same way as antiopa var. hygiaea 

 is obtained. To this purpose I waited till I got some 

 larvae from choke cherries so I was sure they would 

 not be dissippus as the differences in the larvae of 

 these two species are very insignificant. After they 

 had fastened themselves to change into the pupa stage 

 1 placed them in an icebox and there they w^ere left 

 for one week. Some could not be induced to change 

 under these conditions so I took them out again till 

 they changed into pupae and then I placed them back 

 in the icebox. From about 60 caterpillars treated in 

 this way only one var. albofasciata emerged and one 

 specimen with white stripes on the forewings but nor- 

 mal hindwings. The others did not approach at all 

 the whit{;-banded variety. 



I hope to be able to repeat the experiment again 

 next year. 



Concerning the food plants 1 am convinced that 

 the caterpillars of astyanax. feed as well upon wil- 

 lows and Cottonwood as upon cherries. In July I 

 found far out in the prairie and half a mile from any 

 other tree or shrub, a cottonwood tree and on its bark 

 a caterpillar which I supposed to be disippus. I fed 

 it with cottonwood leaves and after ai)OUt one week 

 it pupated and after ten days more there emerged a 

 fine astyanax specimen of more than 3 inches expan- 

 sion. Later I found in another place on the prairie 



