322 



R HO PA L 0 CERA MALAYANA. 



a stout medial spur. Larvre atoat, srjbevlindrical ; the prothomcic 

 segment furnished with two retractile tentacles.* 



Anterior wings having the lower discoidal nervule united to the 

 median nervure, and thua appearing as a fourth median nervule. 



The Papilionina, by the above detailed characters, arc the 

 most distinct and easily recognised subfamily of Khopalocera. 

 ^j^WA^K The W*™&y four-branched median nervure of the anterior 

 "" t% "' 1 n - wings ia found in no other group of butterflies, and is a 



neural feature of so simple and clear a character that a glance at the wings is sufficient to 

 decide whether a butterfly belongs to the Papilioninm or not. The larvae, again, possess an 

 extraordinary organ iu a Y-shaped tentacle situate on the prothoracic segment, which, 

 concealed in a state of repose, is capable of being suddenly thrown out by the caterpillar when 

 alarmed. On this point Mr. Wallace has well remarked " When we consider this singular 

 apparatus, which in some species is nearly half an iuch long, the arrangement of muscles for 

 its protrusion and retraction, its perfect concealment during repose, its blood-red colour, and 

 the suddenness with which it can be thrown out, we must, I think, be led to the conclusion 

 that it serves as a protection to the larva, by startling and frightening away some enemy when 

 about to seize it, and is thus one of the causes which has led to the wide extension and 

 maintained the permanence of this now dominant group-" t 



This subfamily includes but few genera, its strength lying in the genus Papilla itself. 

 Three genera — or, as treated here, two genera and one subgenus — are found in the Malay 

 Peninsula, and, excluding Tci no palpus, J there is little probability of more being found, 

 as the others are principally denizens of higher altitudes. These three genera, however, 

 viz*, Qrititkoplera t Papiiio, and Leptocircus, are of very unequal value, the first two being 

 almost inseparable, in a structural sense, if we retain the genus Papiiio in its old and 

 undivided condition. There can be no question that in Papiiio, as thus understood, we 

 do find structural and neural characters that in other subfamilies are ranked as correctly 

 proving the existence of distinct genera, and which, if the useful though artificial canons 

 of classification were here rigidly adhered to, would compel the generic disintegration 

 of Papilio.% The objections, however, to that course appear to have at least considerable 



* Prof. Wcetwod (Introd. Mod. Class. Ins. vol. ii. p. M*\ states that the larva* are •* never villus nor hairy," but this 

 doe* nut nppe&i to be always true in the earlier id a go* of development, as Mr. I'ursayetli ih*cvil><-s the young larva- of lUtpilio 

 erithoniu* as differing greatly "from the mature caterpillar, having numerous processes, armed with stiff bairn or whines, 

 along either aide and head'" (Trans. Eut. Soc. 18B4, p. 8*»). 



1 Trans. Linm Hoc. vol. xxv, p, 8 (18fi5). 



The use of this organ has been observed iu the common Pahe arctic butterfly, 1'itpUi* machaon. Uomna status ihnt 

 when he pressed thin caterpillar, neiir its anterior part, it darted forth its horn as if it nn ;mi to prick him with it. directing it 

 towards in^ tinkers; but withdrawing it it* mhhi us he left otf pressing it. " This Imrn tuiu-!l> hln.-nu'k of fennel, itinj probably is 

 employed by the insect, by means of its powerful scent, to drive away the Hies and ichneumons that annoy it " (Kirby & Spcnce, 

 Introd. Ent. 7th etl. p. 118). lteunie ubscrvod the same action in larvw of the bnttertly foil ml feet ling on fennel in theJurdin dee 

 Pinnies at Paris, and concludes that it might be "intended tu intimidate the ichneumon* from depositing their parasite eggs 

 in it* body, or warning oil the thrushes or the carnivorous locust (Acrida vomtcivora) from devouring it- On the same plant 

 indeed where these caterpillars were feeding we saw one of the latter larking about, im doubt with evil inn ni" (/ Ineect 

 Miscellanies),' pp. 63-4), Mr. Forssyeth describes the hirvui of Papiiio crittiottitt* its fi<und at Mhow, in CVtitra] India, and 

 speaking of these tentacular states that "on pressure between finger and thumb, a double horn, soft and erectile, of a pink 



colour, shoots out and tpiivers slightly When extrusion takes place a rather pungent, aromatic, but certainly not 



disagreeable, odour is given out. The larva seldom shoot forth these processus on being handled or irritated, but only on 

 pressure being made" (Trans. But- Soc. 1884, p. 'Am). The odour thus emitted is not, however, always pleasant, as Laourdmre 

 has informed us: — "Dons cerlaiues ttpfoes Amoricaines {Papiiio Craztui, Archetatts* &o.) t que nous avous eu occasion 

 d'observer, cette odeur eat plus uu innins desagreablu " (Introd. a 1'eutomoL i. p. 108). 



[ A genus found in North-Eastern India. 



§ The Ceylon species have thus been treated by Mr. Moure iLep. Ceylon, vol. iJ. 



