BUTTEEFLIES OF SAMOA AND SOME NEIGHBOURING ISLAND-GROUPS. 59 



21 o, and 17 mm. ; all except three of the females have no blue markings at all 

 (these three have no more than a slight powdering of blue on the forewing, 

 and none on the hindwing), and the black spot at the anal angle is present in 

 all except two of the males (in both series it is always present in the female). 

 These differences do not appear, however, to be geographical, for a series of 

 seven males and one female taken in Togatabu, Haapai, and Vavau, in 1925 

 and 1926, exactly resembles the Samoan specimens, the maximum, mean, and 

 minimum expanse being 24, 21 '5, and 18 mm., while the black spots are present 

 in all ; the single female is of the Samoan form, with no blue markings. In 

 both series the sexes are alike in size. 



Never a very common species in Samoa, but found sparingly in Upolu 

 wherever the food-plant, Indigofera anil L. (Leguminosae) occurs ; Water- 

 house records it also from Satupaitea in Savai'i. The food-plant is a common 

 pink-flowered shrub, which is confined to the coastal region ; I did not see it 

 in Tutuila, and have no records of Z. alsulus from there. It is not much 

 attracted to flowers, and never found away from the immediate neighbourhood 

 of the food-plant. In Tonga it was not uncommon at Nukualofa, and I also 

 took it in Haapai and Vavau. 



Egg placed very carefully in between the crowded buds of an inflorescence ; 

 bright green when laid, rapidly fading to very pale green approaching white ; 

 covered with rather coarse sculpturing of the " honeycomb " type usual in 

 Lycaenid eggs ; diameter 0*45 mm., height 0"27 mm. 



Larva slug-shaped, pale green, head pale brown ; there is a rather distinct 

 dark brown mid-dorsal line, and a yellow spiracular line ; spiracles brown, 

 legs and prolegs green. 



Pupa green, dorsal surface thickly sprinkled with small blotches of 

 brownish-olive ; attached by means of a silken girdle and tail-pad to either 

 surface of a leaf. The imago hatches after six or seven days. Several of the 

 pupae were parasitised by a Chalcid. Early stages were found in September, 

 November, and December, and would probably have been found in every 

 month if properly sought for. 



Mathew gives a detailed description of the larva and pupa, which differs 

 in some respects from mine ; he does not state their provenance, but it appears 

 to have been Tonga ; my notes are from material collected in Upolu. 



