116 



SECOND ANNUAL REPORT OP 



THE PHILENOR SWALLOW-TAIL— Papilio philenor, Drury. 



(Lepidoptera Papilionidao.) 



There is a genus of climbing plants (the Aristolochias), which is 

 peculiarly attractive on account of its large, rich tropical-looking 

 foliage. The Aristolochias are represented in almost all parts of the 

 world, and some of the tropical species bear beautiful and immense 

 flowers. In this country we have three native species which produce 

 but small, pipe-like flowers, but which mak« very pretty ornaments 

 for covering walls and arbors or for ornamenting trellises and 

 screens. The most common and best known species in this State is 

 the go called Dutchman's Pipe {AristolocJiia sipho),hut the two other 

 ^ [Fig. 84] species {A.serpentaria and A. tomentosa) are also 



cultivated. 



In the beautiful botanical grounds of Mr. 

 Shaw, at St. Louis, there are some magnificent 

 specimens of the Dutchman's Pipe, and about the 

 end of last July, these had all been suddenly defo- 

 liated. I was invited to go and examine the cause 

 and propose some remedy. I found the vines lit- 

 erally denuded, for there was not a whole leaf 

 upon them, those that were not entirely eaten off 

 down to the stem, being riddled with different 

 sized holes. Upon a close examination, the au- 

 thors of the mischief were soon found, in the shape 

 of the peculiarly horned caterpillar, represented 

 at Figure 84; but as there were few large speci- 

 mens to be found, it was quite evident that the 

 great bulk of them had acquired their growth, and 

 had already left the vines for some more sheltered 

 situation, in which to transform to the chrysalis 

 state. There were, however, a sufficient number of smaller or more 

 recently hatched individuals, had they remained undiscovered, to have 

 soon taken every vestige of the few imperfect leaves remaining; 

 while the beautiful butterflies which produced these worms were 

 noticed flitting around the vines. 



This insect is found on no other plants but the Aristolochias. 

 The worms commence to hatch in this latitude by the beginning of 

 July, from eggs deposited on the leaf; and individuals may be found 

 as late as the last of August. They live in company, especially while 

 young, and cover the leaves with zigzag lines of silk, which enable 

 them the better to crawl about and hold on to the vines. The newly 

 hatched worm is dark brown, with no spots, and with quite short 

 tubercles. After the first month they become lighter colored, with 

 the tubercles on the back of segments 6, 7, 8 and 9, of an orange 

 color, and some of the other tubercles, especially the two on the first 

 segment, proportionally longer than the rest. After the second 



