88 



Papilio Ajax. First Stage (fig. i6). The color of the httle cater- 

 pillar is very dark, probably black. Four row.s of warts appear on each 

 side, — dorsal, sub-dorsal, supra-stigmal and infra-stigmal. Only a sin- 

 gle bristle stands on each of the small dorsal warts, while the others bear 

 many. The bristles on the upper rows of warts are very long, and of 

 a peculiar form, having a furcate division at the extremity. In this 

 they entirely differ from the form of bristles seen in the first stages of 

 the other Papilionidce^ which have a shovel-formed enlargement. 

 Nevertheless they may be traced back to the latter, since they are 

 formed by the division of an enlarged extremity. 



Second Stage (fig. 17). This stage seems scarcely to differ from 

 the first; the general color, as well as the form of the warts and bristles, 

 is exactly the same as before the moult. 



Third Stage (fig. 18). The change from the second to the third 

 stage is an abrupt transition. The color has been suddenly altered ; 

 instead of the uniform dark hue, the ground color is now quite bright, 

 and is interrupted by a large number of black bands, four of which are 

 seen on every segment. The lower part of each ring is enclosed by 

 two curved longitudinal stripes. The warts and the long forked bristles 

 have suddenly vanished, and the skin appears quite smooth. I have 

 a preparation in Canada-balsam, in which the skin is just beginning to 

 be loosened, so that under it is visible the form of the caterpillar in the 

 third stage; by the aid of a high magnifying power it xxxax be seen that 

 bristles are still present even in this stage, but very small, and without 

 furcation, and in proportion to the size of the body almost in\'isible. 



Fourth Stage (fig. 19). The only alteration in this stage is that 

 the black stripes have become much narrower, and often appear inter- 

 rupted, so that the bright general color is now more prominent; be- 

 tween the last thoracic and the first aV)dominal segment a broad black 

 band appears. 



The Fifth Stage has not come under my notice, but I do not be- 

 lieve that it will be found to differ essentially from the fourth. 



Papilio Philenor. First Stage (fig. 20. I cannot decide with 

 certainty as to the color from alcoholic specimens, though it seems to 

 be dark. The young caterpillar is beset with very long bristles, which 

 stand on small warts. Each wart in the two dorsal rows bears only a 

 single bristle, while those in the sub-dorsal, supra-stigmal and infra- 

 stigmal rows bear several. In addition to these there are also stout 

 bristles on the head, the last abdominal segment below the infra-stigmal 

 row, and finally on the thoracic feet. Two different kinds of bristles 

 can be distinguished, namely: those having an enlargement above 

 (fig. 20a), and others which run to a point. The latter seem to be the 

 more numerous, while the former are confined to the dorsal and sub- 

 dorsal rows of warts. 



