496 MR. H. W. BATES ON THE LEPIDOPTERA 



structure of tlie anterior legs in tlie adult state of the insects. The Seterocera have 

 always six perfect legs : most of the families of Rhopcdocera have the anterior pair in a 

 more or less rudimentary condition ; and as the atrophy seems to have reached its furthest 

 stage in the Heliconida, this group must he considered as occupying the highest rank in 

 the order. Other characters accompany the one derived from the structure of the legs, 

 which it is unnecessary here to enumerate. It will he seen from these remarks that the 

 order Lepidoptera is one of those groups in the Animal Kingdom which show, heyond the 

 many collateral branches of development that always exist, a clear linear advancement 

 of organization. 



The Heliconidce, Danaidce, and Acrceidce are related to each other in a different way 

 from that which appears in the received classifications. A few remarks on their mutual 

 affinities are necessary, in order to exhibit the true relations of the Heliconidce to the 

 allied groups of the Old World tropics. It has escaped the notice of all authors, that the 

 HeliconidcB are composed of two groups, which differ very considerably in important 

 points of structure ; in fact, the majority of the genera of which the family is composed 

 ought to be withdrawn from it, and placed with the Danaidce. The very great superficial 

 resemblance between the two sets of genera has led to their being united by all authors, 

 and prevented inquiry into their real relationsliip. To avoid innovation, I will retain the 

 family as it stands, and call the group which is allied to the Dcmaidcs, Danaoid Heli- 

 conidjj:, and the other, which approximates somewhat to the Acrceidce, Acr^oid Heli- 

 conidce. The Acrseoid group comprehends the genera Seliconius and Eueides; the 

 Danaoid, the whole of the remaining HelicomdcB. The following are the distinguishing 

 characters of the two groups : — 



Acrceoid Heliconidce. The hind wing-cell is very small, and the nervures are so 

 arranged that the upper and lower radials* (discoidal nervures of Doubleday) appear 

 to be branch and sub-branch of the subcostal nervure, the discocellulars being short 

 and continuous with them ; the costal nervure is prolonged to the apex of the wing. 

 The larvae are similar to those of Acrcea and Argynnis [Nymphalidce), being beset 

 with hispid spines f. The head is broad, the palpi thick. 

 Danaoid Heliconidce. The hind wing-cell is very large, and irregular in shape ; the two 

 radials never appear as branches of the subcostal, but are very uncertain in position, 

 owing to the very vacillating length and direction of the discocellulars : the costal 

 nervure is short, and terminates on the costa, not reaching the apex of the wing. 

 The larvse (only one species is known) are smooth, like those of the Danaidce, but 

 are furnished with tubercles, instead of long fleshy threads. Head small, orbicular ; 

 palpi slender J. 



* I have adopted the terminology of Doubleday (Doul)l., Ilewits., and Westwood's Genera of Diurnal Lepidoptera) 

 with regard to the neuration or veining of the wings, excepting that I call the " nervules " of the subcostal and 

 median nervures "branches," and the "discoidal nervures" "radials," these alterations appearing necessary to 

 prevent the verbal confusion of nervule vnth nervure, and discoidal with discocellular. 



-j- The early states of these insects were not known to Doubleday. I reared, myself, Heliconius Erato (and Doris) 

 and Eueides Lybia. We are acquainted, through other sources, with the larvse of //. Melpomene, H. Ricini, and 

 Mechanitis Polymnia. 



X Since the above memoir was read. Dr. C. Felder of Vienna, in an article entitled, "Specimen Faunae Lepidopte- 

 rologicse riparum Negro superioris in Brasilia septentrionali," 'Wiener Entomologische Monatschrift,' March !86'2, 



