1948] 
Banks — Perlidcc 
115 
width. In female the prongs are extremely broad at base, 
and with a short point, or slender peg at inner corner. 
Each lobe of the subgenital plate is rounded, but not as 
hairy as in nitida. 
Besides the four species mentioned are two new species ; 
one from the streams on the higher slopes of the Smokies, 
and another the only form seen from New England. 
Perlesta placida nitida new race 
Head and thorax above black, shining, on head there is 
a pale yellowish spot between eye and hind ocellus, and on 
margin over base of antennae the ridge is yellowish, some- 
times the spot by the eye is smaller, or almost gone, and 
the ridge only partly yellowish ; abdomen dull black above, 
below paler on venter, and on sternum dull yellowish, also 
on under side of legs, above on legs brown to black, tarsi 
black ; antennae dull yellowish on basal third of fourth, be- 
yond brown; setae yellowish on first five or six joints, then 
more or less brown to blackish on basal half to three- 
fourths with the tip pale, further out thejoints are wholly 
black. Wings blackish, costal area pale yellowish, veins 
black. 
Structure similar to placida; hind ocelli a little nearer 
to eyes than to each other, lateral boss transverse and 
placed as in placida; pronotum in female about twice as 
broad as long, in male not so broad, narrowed behind, with 
strong rugae on each side ; hind femora fully as slender as 
in placida, much more slender than in cinctipes, the west- 
ern black species. 
The male genital prongs are shorter, more straight than 
in placida and the apical third is the only narrow part ; in 
the female there is a very broad part for the basal three- 
fourths and at inner tip a short, slender apical part. The 
subgenital plate has two lobes, each lobe strongly rounded 
on tip instead of the truncate lobes of other species ; these 
and the apical margin of the ninth segment have many 
long hairs, more than usual. The V-mark shows two pear- 
shaped bodies, with a long stem toward the front ocellus. 
Expanse 18 mm. 
Two females and male from Holliston, Mass., 22, 30 
June, 1 July. One male from Pittsfield, N. H., 5 July 
