BUTTERFLIES OF SAMOA AND SOME NEIGHBOURING ISLAND-GROUPS. 27 



April and May 1925, and Lalomanu, Aleipata district, September and October 



1924. All these localities are in Upolu. 



Variation on the upperside is slight, for a race of H. bolina, and in the 

 female extends at most to the loss of the orange patch on the forewing. Out 

 of 122 females from Western Samoa, only 10 have no trace of this " nerina- 

 red " ; this is certainly more than the true proportion, for the form was noted 

 as being rare, and specimens of it were often collected when those possessing 

 the orange patch were passed over. There is also a little variation in the other 

 direction, the orange colour extending to cover the greater part of the disc of 

 the forewing, but such specimens are not common. The white marks on the 

 forewing are never obscured. There are sometimes traces of orange on the 

 outer side of the white discal spot of the hindwings (in about a third of the 

 females), and rarely this also becomes more extensive, but never produces 

 a form at all like pallescens. On the underside there is a good deal of variation 

 in the width of the white band on the hindwing, which may be well developed 

 or much reduced. An entry in Mathew's diary (" Apia, Samoa, June 20, 

 1884 . . . many bolina, the females varied a good deal ") may perhaps indicate 

 that the race was formerly more variable than is now the case. 



The female is very common everywhere in the coastal belt of all the islands 

 of Western Samoa, and occurs as a straggler in open spaces up to 2,000 feet, 

 but the male is extremely rare, much less than one per cent, of the specimens 

 observed ; only eighteen males were seen during the whole two years, while females 

 were common in every month. Of the specimens captured (about 150), only 

 six were males, and this is much above the true proportion, as a special watch 

 was kept for them. The rarity of the male is so marked as to lead inevitably 

 to a suspicion that parthenogenesis must occur in this race, but unfortunately 

 I was never able to prove this by breeding ; a series of six females, neither very 

 fresh nor very worn and all containing eggs, which were dissected in December 



1925, had no spermatozoa in the spermatheca, but much more of this negative 

 evidence would be required before we could consider the existence of partheno- 

 genesis in the form proved. Simmonds has been unable to obtain larvae from 

 unfertilised eggs in Fiji, but I do not know of any other race of H. bolina in 

 which the discrepancy between the sexes is so great as in inconstans. The com- 

 bined observations of Armstrong and myself show that this discrepancy has 

 been constant over a period of at least four years, while the fact that Rechinger, 

 collecting in 1905, was not able to capture a single male suggests that it is of 



