OCR Text |
Show 6 ME. E. Y. WATSON ON THE HESPERIIDSE. [Jan. 17, as Hesperiidse ; the Australian genus Euschemon, which is furnished with a frenulum, one of the most distinctive characters of the Heterocera, has also been omitted ; should subsequent authors consider these three genera are more naturally placed in the Hesperiidse, it will be necessary to establish two additional subfamilies for their reception. With regard to the vexed question of the generic importance of male secondary sexual characters, the conclusion which has been forced upon me is that, in any particular genus in which male secondary characters are found, the particular male character (be it costal fold, discal stigma, or tuft of hairs) may be either present or absent in different species of that same genus, but is never replaced by a character of different structure. Of the inconstancy of the male character in the same genus the following are examples :- Eudamus, Thorybes, Hesperia, Vrbanus, Ismene, Hasorct, Kerana, Padraona, Taractrocera, Chapra, JBaoris, Halpe, and many others might be brought forward; but on the other hand it is difficult to quote a single genus in which the male character is replaced by another of similar character, and in a few cases where this is apparently the case in the following paper, it is owing to new genera not having been erected for the aberrant forms though manifestly distinct, time not allowing of the critical examination necessary. O n every other occasion when the male secondary character differs in structure, an accompanying difference will be found in the neuration, antennse, or other point of structure. The above being the case, the costal fold, discal stigma, or other structural peculiarity of the male insect, though frequently not a generic character, is yet of the greatest importance in the formation of groups or subfamilies, and, as has already been pointed out by Scudder, all those species which are provided with a costal fold belong to the Hesperiince, and all those provided with a discal stigma to the Pamphilince. Though the above conclusion is not in accordance with tbe theorv of many authors, yet it will be found that no author can be quoted who does not admit it in practice; for instance, Scudder places bathyllus and pylades in the same genus Thorybes, though the former is without a costal fold and the latter is provided with one; Mabille, in his paper above quoted, includes in the genera Thymele] Eudamus, JEthilla, Ismene, Pamphila, and others species both provided with and devoid of male secondary characters ; Moore, w h o is one of the strongest advocates for the generic importance of male characters, yet, under the same generic name Thanaos, describes indistincta and stigmata, the former of which lacks the discal stigma of the latter, includes in his own genus Halpe the species radians, though without the discal band characteristic of the genus, describes atkinsoni, subtestaceus, nilgiriana, and vindhiana, all as belonging to the genus Isoteinon, though the two former possess a tuft of hair* on the fore wing which is wanting in the latter, and acts similarly on several other occasions; while Distant and Trimen in their respective works allow to male characters no generic importance |