62 



Mr. A. R. Wallace on 



men slender. Anal valves of the male elongated and provided 

 with a tuft of long and stiff hairs at each side at the base beneath, 

 as shown in the accompanying figures, compared with the same 

 part in allied genera : — 



FigZ. 



Fij3- 



Tiq^. 



1. Tachyris nathalia, Felder. 



2. Taclnjris nero, Fabricius. 



3. P'ler'is agathon, Gray. 



4. Pieris ieutonia, Fabricius. 



Upper wings with the apex acute or much produced, two subcostal 

 nervules given off before the end of the cell, the third of moderate 

 length or very short, and in some species quite wanting ; upper 

 radial as a branch of the subcostal at some distance beyond the 

 cell. Sexes often differing widely. Larva hairy, and with four 

 or six longitudinal rows of spines ; pupa with two lateral 

 spines. 



This genus does not differ materially in neuration from Pieris, 

 but the remarkable character of the strong tufts of hair at the 

 anal valves of the males enables us to bring together a number 

 of allied forms, which, whenever the male sex is obtained, can be 

 referred to the genus with the greatest certainty. It is restricted 

 to the tropics, but comprises species from all the great divisions 

 of the globe, and is particularly abundant in the Indian and 

 Australian regions, comprising more than fifty species. The 

 African species sylvia, Fab., and cudoxia, Drury, belong to 

 this genus, and a few others allied to them ; while in South 

 America, viargarita, Hiibner, and several closelyallied species, 

 appear to be its only representatives. In the Malay Archi- 

 pelago, besides a host of species which present the usual 

 white or yellow tints of the family, it contains others whose rich 

 hues of cinnabar-red, orange, and greyish-blue, are altogether pe- 

 culiar. Most of the species fly swiftly, and many of the males 

 assemble in troops about wet places and on river margins, after 



