40 riEHILLE. 



Genus IV. PONTIA Boisd. 

 Boisd. Sp. Gen. i. 430. (1836). 



Pontia Fab., M'Leaij. 



PlERIS GO'I'. 



Head rather small, the forehead clothed with scales and short hairs. 



Eyes large, round, very prominent. 



Labial Palpi longer than the head, scaly, densely furnished with long hair in front, l'asal joint 

 elongate, subeylindric, curved at the base, perhaps rather widening towards the apex, which is 

 truncate ; second joint nearly half the length of the first, oval, truncate at the base ; third joint 

 shorter than the second, very slender, fusiform. 



Antenna rather long, with a compressed fusiform club. 

 Thorax slender, clothed with small scales, mingled posteriorly with short hairs. 



Anterior Wings rounded anteriorly and outwardly. Subcostal nervure three-branched ; its first 

 nervule thrown off about the middle of the cell ; the second more than half-way between this 

 and the end of the cell. Upper discoidal nervule united to the subcostal for a space about equal 

 to that between the second subcostal and the end of the cell. Middle disco-cellular very short ; 

 lower long, curved inwards. Cell large. 



Posterior Wings large, obovate. Discoidal nervure appearing to be a third subcostal. Disco- 

 cellular nervule long, curved. Trecostal nervule not branched, curved outwards. Cell ample. 



Legs elongate, slender. Paronychia nut so long as the claws, broad, subtriangular. Pulvillus 

 jointed, as long as the claws. 

 Abdomex slender, elongate, but not extending beyond the posterior wings. 



This genus is confined to the tropical parts of the Old World, where it seems to replace Leucophasia or Leptalis. 

 In the delicate texture of its wings it resembles the former genus, and some species of Leptalis as Lept. Vocula, but 

 differs from both those genera by very marked characters. 



Its three-branched subcostal nervure and long pulvilli separate it from both these genera, and from the latter it is 

 likewise distinguished by its longer palpi. 



Its nearest allies are some species of Pieris, but its shorter palpi and the fusiform club of its antennae readily 

 distinguish it from them. 



The few species known are all of a delicate pearly white, with the apex of the interior wings black above; mostly 

 there is a round spot of the same colour near the outer margin, and the costa is freckled with fuscous. Below, the 

 apex and base of the anterior wings, and the whole surface of the posterior, are more or less tinged with greenish yellow 

 freckled with delicate olive green dots, disposed in clouds or transverse bands. The cell of the anterior wing is marked 



