148 



first moulting, closely resemble in form and in their tubercles, 

 the figures of the larva of Ornitlwptera Helicaon in Boisduval's 

 Histoire Naturelle des L^pidopteres, taken from Dr. Horsfield's 

 catalogue. After the first, moulting, the first pair of , tubercles 

 increase in length, and become proportionally much longer than 

 the others, and the body itself becomes more elongated. Ab- 

 bot's figure of the full grown larva may be considered as quite 

 correct, except that the last pair of dorsal tubercles should have 

 been curved backwards and outwards, and the yellowish, or 

 rather orange-colored spot on the first segment, should have 

 been placed between the first pair of horn-like tubercles imme- 

 diately in contact with the liead, and not behind them. The 

 pupa is not well done in Abbot's work, and both larva and pupa 

 in Boisduval and LeConte's Ldpidopteres de I'Am^rique are 

 miserably represented. The pupa approaches more nearly in 

 form to that of Ornitlioptera Helicaon than it does to that of 

 any other butterfly known to me. It appears to me that Pliil- 

 enor may be considered as one of the connecting species be- 

 tween Ornitlioptera and Papiilio ; while Podalirius^ Asterias^ 

 etc., come at the end of the latter genus, connecting it with 

 Boritis^ CoUas, etc. The larvge of Philenor live in company, 

 cover the surface on wliich they are about to move with zio-zao; 

 lines of silk, and seem unable t6 crawl or hold on without this 

 precaution ; for when placed on a fresh leaf the least motion 

 causes them to fall off. This is not the case with the larvse 

 of Asterias, which is solitary ; but those of Turnus and Troi- 

 lus, also solitary, cover the leaves on which they live with a 

 complete coating of silk, and bend up the sides of the leaf to 

 form a sort of trough, in which they remain when at rest. 

 Hence the three groups of which these species are the repre- 

 sentatives, differ from each other as much in habits as in the 

 form of the larvas. 



