502 MR. TRIMEN ON MIMETIC ANALOGIES AMONG AFRICAN BUTTERFLIES. 



on as indicating perfection of the Khopalocerous type, when it is considered that the 

 only known instances of an organ similar in structure and function in the rest of the 

 Lepidoptera are found, not in Butterflies of any family, but in Ceriira, a genus of Bom- 

 hycide Moths. The organ of the Puss-Moth caterpillars is double, instead of forked, and 

 occupies the opposite extremity of the body ; but it is plainly homologous to that of the 

 Papilio larvse, and is protruded on occasion in precisely the same manner. Looking to 

 the pupte of the several families, we find, receding from those of the Hcterocera in 

 silken, earthen, or other cocoons, or buried in the ground, a gradual advance, cor- 

 responding with that towards a more aerial type of imago, to the freely suspended chry- 

 salis of the tetrapod Rhopalocera. The pupae of the HesperiidcB are secured, like those 

 of many moths, either in a slight cocoon or by several silken threads ; those of the Fapi- 

 lionidcs, Fieridce, and Lycmnidce*, by the tail and by a single silken girdle; while, 

 through the JEnjc'midce, which present instances both of girt and freely suspended puptet, 

 there is a gradation to the chrysalides of the true Nymphalide Butterflies, which hang, 

 head downwards, by a caudal attachment only. The remarkable pupa of Farnasshis, 

 snore heteroceroid (in its blunted form, bluish efflorescence, and numerous threads of 

 support in a cocoon of leaves) than most of those known among the HesperiidcB, seems 

 to afford an additional indication of some connexion between the PapiUonidcB and Moths. 

 Another singular fact tends to strengthen the idea of a remote, liut distinct relationship, 

 viz. that the pupa3 of Ep)hyra, a Geometrine genus, are not only suspended by the tail 

 and a silken girth, in precisely the same position as those oi ihe FajjiUonidce, but closely 

 resemble them in form, M. Guenee observing ('Phalenites,' ix. p. 402) that they can 

 best be compared with the chrysalides of Thais X- Similar, also, in their caudal attach- 

 ment and silken girdle, but not so like the Papilio chrysalides in form, are the pupse of 

 the very curious Heterocerous group of Pterophoridoi, which stands alone in the structiu'e 

 of its wings, and has hitherto, hj common consent, been placed last in the entire order 

 Lepidoptera. 



It thus appears that the Papilionidce exhibit points of structure in common with some 

 Heterocera in each stage of their growth ; and these characters seem, in the aggregate, of 

 suflicient importance to warrant our assigning to the family a position much nearer to 

 the Moths than that which, until lately, has so generally been accorded to it. 



Tm'uing to the Danaidce and Acrmdce, which have so much in common both in struc- 

 ture and habits, it is curious to find how the two families differ in their early states. The 

 larvae of the Old-World Danaidce are smooth, but provided Avith several pairs of long 

 fleshy filaments ; and, from the case of Mechaniiis Polymnia (mentioned by Mr. Bates, 

 loc. cit. p. 196), the Heliconide Danaidce also present a smooth larva, which, however, is 

 furnished with tubercles instead of filaments. The Acrcsidce (of Africa) are, in the 

 larva-state, densely studded with stiff branched spines ; and the true (or Acrasoid) Heli- 



* The larvse of some Lijccmidie (e. g. Theda Quemis, L.) are stated to burj- themselves iu the earth before assuming 

 the pupal condition. 



t See Mr. Bates's 'Catalogue of Eiycinidai,' in Journ. Linn. Soc., Zool. is. p. 368. 



J Plate 2 of M. Guenee's volume gives an interesting figure of the pupa of an EpJii/ra in its natural position. 

 Thais is recorded as having the chrysalis enclosed in a slight web, -which is not the case with Ephyra. 



