12 



INSECTS OF SAMOA. 



erroneous. If the label be correct, it must be a very rare aberration, for there are 

 no specimens showing the least approach to it in any of the collections examined, 

 nor in the long series collected by me in Tutuila ; on the other hand, judging from 

 Fruhstorfer's figure, which does not agree with his description, it almost exactly 

 resembles specimens from the Cook Islands, which are its probable habitat. As, 

 mentioned by Poulton (p. 586), there is in the British Museum a " Male walkeri, 

 with the hindwing pattern of escholtzi" labelled Navigators' Islands ; this has 

 the grey suffusion of the underside typical of bourkei and mathewi, and is probably 

 correctly labelled, but there are no specimens showing any approach to this 

 pattern in the very long series of other Samoan examples examined by me. 



Variation is not extensive, but the spots on the hindwing are slightly more 

 developed in some specimens than in others. Females always have the ground- 

 colour paler than males, but do not seem to exhibit better developed spots. 

 The most interesting point about the race, however, is the occurrence of males 

 with a sexual brand, a feature never recorded before in any race of " helcita." 

 Of twenty-six males captured by Buxton and myself in Tutuila, seven have 

 a well-developed brand (PI. Ill, figs 9 and 10), and two more show a trace of 

 one, so that more than a third of the specimens have the brand developed to 

 some extent. As might be expected in what is evidently a vestigial and 

 obsolescent structure, the brand varies very much in size, but I have never 

 seen a trace of it in the hundreds of male " helcita " from Tonga and other 

 groups in the neighbourhood of Samoa that I have examined. 



The maximum, mean and minimum expanse of twenty-six males are 82, 

 74, and 66 mm., and of fourteen females 76, 70, and 65 mm. 



Common in Tutuila Island, American Samoa, at Pago-Pago, Leone, and 

 other localities at or near sea-level, frequenting the flowers of Ageratum coryzoides 

 and Stachytarpheta ; there are also three specimens in the collection from Tau 

 Island, American Samoa. It is very easily distinguished from E. schmeltzi, 

 even on the wing, by its much darker colour and larger white spots. This form 

 does not occur in Western Samoa ; the types were stated by Poulton to be from 

 " Apia and Tutuila " (E. Bourke) and " Apia and Pago-Pago " (G. F. Mathew), 

 but Mathew, on referring to his note-book, found that all his Samoan specimens 

 of the species were from Pago-Pago, and it is quite certain that Bourke' s speci- 

 mens also came from there, since he lumped the two localities together. 



As represented by its several races, this is one of the most widely-distributed 

 butterflies in the Pacific Islands, often occurring on atolls which support no 



