THE BUTTERFLIES OF NEW ENGLAND. 



THE LARVA OR CATERPILLAR. 



]}orii, lired, with just one instinct, — that of urowtli: 



Her quality was, (•atori)illai--like, 



To ali-unerrinuly select a leaf 



And without intermission feed her fill, 



Keconie the Tainted Peacock, or belike 



The Brinistone-winu', when time of year should suit; 



And 'tis a sijin (say entomologists) 



Of sickness, when the creatui'e sto])s its meal 



One miiuite, either to look up at heaven, 



Or turn aside for chanji'e of aliment. 



J'.uowxixG. — 7?<?rf Oittan Xi(/ht-Cap Conntrii. 



External form and characters. 



Caterpillars of butterflies differ in no single feature from those of motlis. 

 In oeneral, they may be said to be long, cylindrical and uniform, usually 

 more or less flattened beneath, and to be composed of two regions, perfectly 

 distinct from each other, — a head and a body : the former is a horny, com- 

 pact, more or less appressed, globular case bearing numerous appendages 

 about the oral orifice ; the l)ody is divided into thirteen nearly equal fleshy 

 seo^ments, the anterior three of which form the future thorax, bearino" each a 

 pair of more or less horny fiye-jointed legs, armed at tip with a simple claw ; 

 the others, \vhich form the future abdomen, being proyided on the third to 

 the sixth and the last segments with a pair of stout fleshy prologs or stumps, 

 bearino- at the ti[) a series of minute hooks ; all the segments of the body 

 arc proyided with hairs, tubercles, s[)incs or filaments, and some with lateral 

 openings, — the s])iracles or breathing ]»ores. 



The head and its appendages (87:1G). The head is divided by a 

 suture into two lateral halves, but near the middle of the front this suture 

 divides and leaves between its forks a triangular space, the frontal triangle 

 or clypeus, which is often characteristically marked : it is down this middle 

 suture that the head splits when the integument is cast for })upation ; at 

 previous exuviations the head is cast entire, but at the final moult the two 

 hahes are parted ; just within and parallel to this forked suture, forming 

 the lateral Avails of the frontal triangle, is another more deeply impressed 

 line, which would readily be taken fi)r the suture, since the markings are 

 distributed in relation to this rather than to the other ; it is, howcAcr, simply 

 the reverse of an interior ridge for the support of muscles ; the true suture 

 is almost always very inconspicuous and can often hardly be discovered in 

 the earlier larval stages (78-80). The two can best be seen in Anosia. 

 Just below the triangle and as broad as its base is a -very short piece, gen- 

 erally inconspicuous and welded to the triangle, most distinct in the Papili- 

 oninae, called the e})istoma, to the lower edge of which the labrum is 

 attached ; the latter is usually bilobed by a yery deep excision of its front 

 border, generally narroAAcr than the epistoma, to \\hich it is attached by a 

 fleshy hinge, is always broader than long and moACS freely I)ack and forth 



