The Life-History and Anatomy of Butterflies 



pillars have long, 

 thickest about the 



worm-like bodies. Frequently they are 

 middle, tapering before and behind, flat- 

 tened on the under side. While the 

 cylindrical shape is most common, there 

 are some families in which the larvae 

 are short, oval, or slug-shaped, sometimes 

 curiously modified by ridges and promi- 

 nences. The body of the larvae of lepi- 

 doptera consists normally of thirteen rings, 

 or segments, the first constituting the 

 head. 



The head is always conspicuous, com- 

 posed of horny or chitinous material, 

 but varying exceedingly in form and 

 size. It is very rarely small and retracted. 

 It is generally large, hemispherical, 

 conical, or bilobed. In some families it 

 is ornamented by horn-like projections. 

 On the lower side are the mouth-parts, 

 consisting of the upper lip, the mandibles, 

 the antennae, or feelers, the under lip, the 

 maxillae, and two sets of palpi, known as 

 the maxillary and the labial palpi. In 

 many genera the labium, or under lip, is provided with a 

 short, horny projection known as 

 which the silk secreted by the cater- 

 pillar is passed. On either side, 

 just above the man- 

 dibles, are located the 

 eyes, or ocelli, which 

 in the caterpillar are 

 simple, round, shining 

 prominences, generally 

 only to be clearly dis- 

 tinguished by the aid 

 of a magnifying-glass. 

 These ocelli are fre- 

 quently arranged in series on each side. The palpi are organs 

 of touch connected with the maxillae and the labium, or under 

 lip, and are used in the process of feeding, and also when the 



Fig. 12. — Caterpillar of 

 Papilio philenor (Riley). 



the spinneret, through 



Fig. 13. — Head 

 of caterpillar of 

 Papilio aste- 

 rias, front view, 

 enlarged. 



Fig. 14. — Head of caterpillar 

 of Anosia plexippus, lower side, 

 magnified 10 diameters: lb, la- 

 brum, or upper lip; md, mandi- 

 bles; mx, maxilla, with two 

 palpi; Jin, labium, or lower lip, 

 with one pair of palpi; s, spin- 

 neret; a, antenna; 0, ocelli. 

 (After Burgess.) 



