PAPILIO. 93 



spines at the apex, and the claws undivided : hinder 

 wings scolloped, and furnished with a long narrow 

 projecting lobe like a tail ; their interior edge con- 

 cave or grooved, to receive the abdomen. The ca- 

 terpillars are smooth and naked, and often ornament- 

 ed with very beautiful colours. They have the power 

 of protruding from the neck a soft fleshy horn, which 

 divides near the middle into two branches, like the 

 letter Y. This appendage might be supposed to 

 serve the same end as the horns of the snail, to which 

 it bears much resemblance, but, unlike that animal, 

 the caterpillars are said to push it forth only when 

 alarmed, and it has therefore been regarded as a 

 means of defence, the more especially since it dif- 

 fuses a penetrating and disagreeable odour. The 

 caterpillar of P. Machaon, with the horns exserted, 

 is represented on Plate III. fig. 1. 



The chrysalis is angular, and fixed by a silken 

 band round the middle. 



These insects composed the section which Lin- 

 naeus distinguished by the name of Equites. Nearly 

 200 species have been described, many of which are 

 the largest papilionaceous insects known, and re- 

 markable for the variety and richness of their colours. 

 They abound in the tropical regions of both hemi- 

 spheres, but occur very sparingly in temperate cli- 

 mates. Besides the two which we have figured, only 

 one other species is known to inhabit Europe, viz. 

 P. Alexanor, which, though observed of late years 

 more frequently than formerly, is still extremely rare. 



