38 
SOUTH-AFEICAN BUTTERFLIES. 
lengtH ; costa scarcely arched beyond basal curve ; apex always marked, 
and sometimes prominent and acute ; hind-margin straight, or very 
slightly concave about middle ; inner margin usually slightly concave 
about middle ; subcostal nervure four-branched, — first nervule given 
off some distance before extremity of discoidal cell, short, often joining 
costal nervure near its extremity (^Calypso group), — second long, ending 
not far before apex, given off rather nearer to first than to extremity 
of cell, — third subapical, short or very short, ending at apex or just 
before it (in Bmssicce group exceedingly short or even [P. Daplidice 
and P. Ilellica] wanting), — fourth ending at or a little below apex ; 
upper radial nervule united with subcostal nervure at some distance 
beyond end of cell ; upper disco-cellular nervule very oblique, usually 
considerably more than half as long as lower one, which is transverse 
and slightly curved ; discoidal cell rather broad, truncate at extremity, 
more than half length of wing. Hind-ioings broad, rounded, some- 
times rather elongate anal-angularly ; costa moderately or slightly arched ; 
hind-margin very convex, entire or slightly sinuated ; anal angle 
rounded ; inner margins meeting, and forming a tolerably deep groove 
almost to end of abdomen; first subcostal nervule much arched, given 
off a long way before end of cell ; disco-cellular nervules both oblique, 
the upper one much shorter (sometimes less than half as long), the 
lower one slightly curved. Legs moderately long and thick ; femora 
with fine hair beneath ; fore-tibiae much shorter than femora ; middle 
and hind tibiae about as long as femora, their terminal spurs moderately 
developed ; tibiae and tarsi finely spinulose. 
Abdomen curved, compressed, moderately long and slender, rather 
larger terminally, tufted with silky hair at base on back, and more 
thinly so along middle line beneath ; anal valves in $ sometimes with 
a short terminal curved spine {Ccdypso group) ; in other species, a 
tuft of long bristly hairs beneath, just at base of each a,nal valve. 
Larva. — Bather elongate, shortly pubescent, slightly attenuated at 
extremities ; head small. 
Pupa. — Rather slender ; much attenuated posteriorly ; a more or 
less elevated ridge along middle line of back, and another on each side 
of first three segments of abdomen ; an acute projection in front of 
head ; and a prominent tubercle at middle of dorso-thoracic ridge, and 
on each lateral abdominal ridge on second segment. 
Boisduval's list of this genus numbered (1836) no fewer than 
166 species; Doubleday's (1847), 175. Wallace, after separating 
from it (1867) the extensive sections Thy set, Tachyris, and Prioneris, 
gave the number of described species as 171 ; and if (as I consider 
preferable) Tachyris be not separated generically, the total will be 
raised to 237. Mr. Butler's revision of the genus was first given 
(1870) in Cistulei Entomologica, vol. i. pp. 39—52, and, as amended 
(1872) in Proc. Zool. Soc. Lond., p. 27, he still further divided the 
old genus Pieris into fifteen genera, containing altogether 341 species, 
