156 INSECTS OF SAMOA. 



venation, antenna, etc. It is to be feared that many years must elapse before 

 anything of the kind is done with the mass of exotic material that is awaiting 

 attention ; but fortunately the need is not urgent in connection with the present 

 work, for Moore's Chogada can quite satisfactorily be left with Chora, sens, str., 

 as denned by MeDunnough (loc. cit., p. 19). Its type (0. alienaria Walker) 

 differs chiefly from Chora cinctaria in the rather longer palpus, longer primary 

 pectinations and strongly dilated hind tibia of the <§, and in the strongly marked 

 under side. Vein SC 2 of the fore wing in C. alienaria and its nearest allies is 

 much more rarely connected with SC 3 than in typical, Holarctic Chora, but 

 varies in both groups. The facies of what I have called the " Chogada group " 

 (Indo- Australian and African) is nearly always unmistakable, but I cannot 

 accept it as generic, since there are intergrades in all the characters mentioned ; 

 e.g. C. leucophaea Butler, of Japan, with long pectinations, C. displicata Walker, 

 of Queensland, with non-dilated hind tibia, several species with intermediate 

 palpus, and a few — such as C. fortunata Blachier, of Teneriffe, with intermediate 

 facies. 



The number of species which have been confused under the name C. 

 " acaciaria Boisduval " must be very great. Many of them have been found 

 readily separable by wing-markings, when studied by good observers like Moore 

 and Turner ; but some, which I confess to having supposed to be merely geo- 

 graphical forms, or sometimes even aberrations, are proved by the genitalia to 

 be also totally distinct species. Mr. W. H. T. Tarns, at the British Museum, 

 has kindly made preparations of a very large number of forms, and the results 

 are extraordinarily interesting. But the number that would require examina- 

 tion before any systematic revision could be made continues to increase rather 

 than to diminish, and we must reluctantly relegate to the future all but the 

 barest generalisations. » 



The numerous African forms for the most part differ markedly from the 

 Tndo- Australian, and show on the whole a somewhat simpler type of genitalia. 

 One unnamed Ceylon species, of which only a single example is yet known, 

 possibly originated from the same stem as the African forms, and as regards 

 its genitalia is curiously remote from the rest of the Indo- Australian thus far 

 examined. Only two of the Indo-Australian species seem to be really widely 

 distributed : C. injectaria Walker (Ceylon) = C. sublectaria Walker (Ceylon) 

 = C. compactaria Walker (Singapore), for which probably C. processaria Walker 

 -unfortunately founded on an aberrant $ (Moulmein) — will prove the oldest 



