Lepidoptera.' It Was Founded on a Uuml)Er of Butterflies, Remarkable for the Elongated Shape of Their Wings, and Peculiar (With The
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B W' S C Vaq u s COLLECTION OF William ScHAus © PRESENTED TO THE National Museum MCMV — ^^-v^7 //i<. '"^ ^'"-^ ^., -.^^ r «5 ] ^3 XXXII. Contributions to on Insect Fauna of the Amazon Valley. Lkpidopteu.v : IIelicoxid.e. Hi/ Hexhy AValteu Bates, Esq. (Communicated by the Secretary.) * Read November 21st, hsGl. " Die wissenschaftliche rntersuchung der Natur strebt in den Einzelhciten das Aligemcine zu erkcnncn, urn endlicli dein Gruudc allcr Dinge niiher zu koinincn. Fiir diese Art UntcTsuchungen, die immer das Ziel der N'aturforschung scin sollte, bietet nohl keine Thicrclasse so reichen Stoff als die Insecten." Karl Ernst ran Baer, Address on ihe Opening of the Russian Entomological Society, St. Petersl)urg, May 18()0. 1 HE family llcticoniihe was established by ^Ir. E. Duul)leday in 1817, in D(jubleday and Ilewitson's 'Genera of Diurnal Lepidoptera.' It was founded on a uuml)er of Butterflies, remarkable for the elongated shape of their wings, and peculiar (with the exception of one genus, IIa)na(/r//a,s, wliieli the author placed j)rovisi()iiaUy in the family, op. cit. p. 98) to the intertropical and subtropical zones of America. Many of them had been described l)y the older authors under Heliconia, Media nil is-, and several other ill-delined genera. They had been previously (in 183G) united in a lrii)e, Heliconides, by Dr. Boisduval in his ' iSpecies General des Lcpidopteres ;' but this comjjrehended also the group Acrceiche, which Dou])leday excluded from the family. Linuajus treated them as a s(!ction of tlie genus I'(ipilio, under the name oi Ueliconii. The nearest allies of the Ilelieunida- are the ^Icrwidai ]\\^i mentioned and tlie Danayhe: all are distinguished from th(^ true Nyiiiphalidie by the discoidal cell of the hind wings being always closed by jicrfect tubular uervules. Mr. Doubleday, placing more reliance on the shape of the antemue and the al)doniinal border of the hind wings than on the far uKn'e important character above named, was led to exclude the genus Encides from the J'amily : this rendered the definition of the two groups very dillicult, if not impossil)le, Encides having the wing-cells closed in tlie same way as the lleliconidce. Excepting that I re-admit Eueides, and exclude Eamadri/as, which does not enter into the series of the American Eelicon idee, the family will be treated of in the present memoir as defined in the work above quoted. The position of the Eelieonidcc in the order Lepidoptera may Ije luuhn'stood when I state that in a natural system tin; group would stand at the head of the whole series of families of which the order is ctmiposed. At least, this should be its place according to the view now taken of the order by many systematists, who arrange the families of Ithopalocera, or Butterflies, according to their degree of dissimilarity to the Eeterucci-a, or Moths —in other words, according as their structure shows a lower or a higher stage in an ascending scale of organization. Eor, as the lower families of ^Moths are allied to other orders of insects, tlie further a group recedes from them in structure, the higher is the grade of perfection of tlie Lejiidopterous type which it exhibits. The families show their degree of aflinity to JMotlis by many characters, the jiriiieipal of which is the * The materials on which this memoir is founded were collected l)y the author iluring eleven years' research on the banks of tlic .\niazons. vol-. XXUI. 3 X i^^qb^-fc — 196 MR. H. W. BATES ON THE LEPIDOPTERA structure of the anterior legs in the adult state of the insects. The Ueterocera have always six perfect legs : most of the families of Rhopalocera have the anterior pair in a more or less rudimentary condition ; and as the atrophy seems to have reached its furthest stage in the Ilelicontdte, this group must l)c 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 Ije 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 Seliconidce, Danakl(e, and Acrcekhe are related to each other in a different way from that which appears in the received classifications. A few remarks on their mutual afiinities are necessary, in order to exhil)it the true relations of the IIeHco)iklce to the allied groups of the Old World tropics. It has escaped the notice of all authors, that the Ilelicouklce are composed of two groups, which differ vei*y consideralily in important l)OLiits 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 Dunaklcc. The very great superficial resemblance between the two sets of genera has led to their being united by all authors, and j^revented inquiry into their real relationship. To avoid innovation, I will retain the family as it stands, and call the group which is allied to the Danaklce, Daxaoid Heli- coNiDiE, and the other, which a})proximates somewhat to the Acrceklce, Acr.eoid Heli- coxiu.^. The Acrajoid groixj) comprehends the genera HeUcoiiius and Etiekles; the Danaoid, the whole of the remaining Uelkonkhe. The following are the tUstinguishing characters of the two groups : Aci'ccokl HeVieon'ulte. 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 nerviu-e is prolonged to the apex of the wing. The larvie are similar to those of Acrtea and Argynnis (Ni/iiqjhalkhs), l^eing beset with hispid spines f. The head is bnjad, the palpi thick. DaiKiohl UcViconklcB. 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 larvte (only one species is known) are smootli, lik(> those of the DaimkJiC, l)ut are furnished with tubercles, instead of long fleshy threads. Head small, orbicular; palpi sli'nder|. * I liavo addpti'd tlu' terminology of Doublcilay (Doiibl., Ilewits., ,iiul WestwooJ's Geiipra of Diurnal Lepidojjtera) with ri'j^ard to the ucuratiou or veining of the wings, excepting that I call the " nervnles " of the subcostal and median neivnres "branches," and the "discoidal nervures" "radials," these alterations appearing necessary to jirevcut the verbal confusion of nervule with nervure, and discoidal with discocellular. f The early states of these insects were not known to Uoubleday. I reared, myself, IlcUronius Eratii (and Doris) and Eucidcs l/ijlna. M'e are aecjuainted, through other sources, with the larvic of //. Mfliximeiic, II. Riciiii, and Mcchtniitis I'lihjninia. X Since the above nuinoir was read, Dr. C. Felder of N'ienna, in an article entitled, "Specimen Faun;u Lc]iidopte- ri'liigiex ri|iarnm Negro snperioris in IJrasilia se|itentrionali," ' Wiener Eutomologische Monatschrift,' March 18G2, OF THE AMAZON VALLKY 497 This view of the affinities of the family will make a great diiference in the conception of the group as regards the affiliation of the forms. Instead of heing a group isolated in its structure, and peculiar to the tro])ical parts of America, it results that the hulk of thi- genera have a very close relationship to the JJanaidce, vhicli are i'ound in all hot countries of hoth hemispheres: the Acucokl llcUconkhe alone are an isolated set of forms. The American productions, however, show a great superiority in structure and in the diversity of the foi-ms over those of the Old AVorld. In Africa only one genus occurs, namely, Da/iais. In the tropical parts of Asia four genera are found, l)esides Danais ; these are Icleopsis, Ilcstia, EitpUea, and llamadryas, which contain together 74 species. In the hot parts of America IG genera (of Danaoid HelicoiiidcB) have heen discovered, comprising 233descrihed species. l?esides this greater diversity of generic and specific forms, the American ])roductions show a much greater advance in organization than those of the Old AVorld ; in other words, they recede further from what may he considered as the common type, namely, J)(i>i<(is. This is clear from the great and progressive modification in the position of the radial nervures and discocellulars of the hind wings, and the advanced stage of atrophy of the male fore legs reached hy most of the genera. In all the Asiatic genera the fore legs are in the same condition as in Ddiiais and the Xi/i/i- phalhhe. The following Tahle Avill show the relative value of the productions of the two liemispheres in a clearer manner. I have placed tlu^ genera in accordance with Avhat seem to he their mutual affinities. The relative length of the lines between them is a rough expression of th(> degree of relationship. The collateral lines of connexion are also attempted to he expressed. DANAin*. Asia. Africa. America. Danais (.'il sji.) Danais (lOsfi.) Danais (8 sp.) Ideo]) is (2 s,..) I Kuplcca ( J8sp.) Ilestia (12s]i.) Dan AOTD IlEMCONID-t. Lvcorca (fi sp.) Ituna (3sp.) Ilamadryas (-' sp.) 1thona (3 sp.) Thvridia (;i s]..) Kutresis (1 s]i.) .