314 Mr. A. R. Wallace o/z 



Pieris is in having the anal valves of the male more or less 

 spined. The same character, wliich is not mentioned by Wallen- 

 gren, is found in P. meserit'ina, Godt., P. coronea, Cram., and allies ; 

 the South American P. mornisle, P. ausia, and others, also have 

 it, and it reaches its maximum in P. lycimnia, Cram., in which the 

 long acute curved spines are very conspicuous ; but the character 

 is quite an isolated one and varies too much in degree and is too 

 difficult of determination in many cases to serve as a chief generic 

 character. I therefore keep these species as a section of true 

 Pieris, 



My divisions of the genus Pieris of authors may be tabulated 

 as follows : — 



A. One branch of the subcostal nervure 



before the end of the cell . . . . Thyca (2). 



AA. Two branches of the subcostal nervure 

 before the end of the cell. 

 B. Males with tufts of hairs or bristles 



at the anal valves . . . . Taciiyris (3). 



BB. Males with the anal valves bare. 



C. Males with the costa serrated Prioneris (4). 

 CC. Males with the costa smooth. . Pieris (1). 



Of the external affinities of the Pieridce it is impossible to say 

 much. They have no direct relation to any other family than 

 the PapilionidcB, and even with those there is no good connecting 

 link. The European genera Zegris and Thais are perhaps the 

 nearest, since they not only offer some approximation in the 

 structural characters of the imago, but agree also to some extent 

 in their metamorphoses, the larvae of both genera enclosing them- 

 selves in a delicate web. 



In the following list of species I have endeavoured to arrange 

 them in a natural series, and have described the new forms chiefly 

 by comparison with well known types. I have not thought 

 it necessary to burden the Catalogue with many synonyms, but 

 have in most cases referred only to Boisduval's " Species Gene- 

 ral des Lepidopteres" and to Vollenhoven's Monograph for the 

 species mentioned by those writers, except in cases in which 

 there has been confusion of sexes, varieties, or general synonymy. 

 To avoid confusion between two works with almost identical 

 titles, I quote the first (quarto) Catalogue of the East India Com- 

 pany's Museum, published in 1829, as, " Horsfield, Cat. Lep. 

 E. I. C. ;" and the second (octavo) Catalogue of 1857, as, "Moore, 

 Cat. Lep. E. I. C." To make the list of described species in the 



