NO. 3660 MICROLEPIDOPTERA, XVII—CLARKE 51 
anterior edge V-shaped, solidly fused with posterior margin of seventh 
sternum. Antrum not differentiated. Inception of ductus seminalis 
from middle of bursa copulatrix. Ductus bursae bent, sclerotized 
for its entire length. Accessory bursa arising at juncture of ductus 
bursae and bursa copulatrix. Bursa copulatrix heavily sculptured 
from juncture with ductus bursae to beyond middle; anteriorly and 
laterally clothed with a mass of short, stout spines. 
Holotype: U.S. National Museum No. 69753. 
Type-locality: Peru, Cusco, Machu Picchu. 
Distribution: Known only from the type-locality. 
Described from the male holotype (5.]1.1959, J. F. G. Clarke), 
and 2 @ 2 paratypes all from the same locality. The females are 
dated ‘6.11.1959.” 
This species is superficially very similar to Phalonia sublimis 
Meyrick but differs widely in the genitalia. The female genitalia of 
diamphidia are solidly fused with the posterior margin of the seventh 
sternum, those of sublamis are not; moreover, the ostium of diamphidia 
is markedly asymmetrical, that of sublimis is not. The male of sub- 
limis is not known, but the male genitalia of diamphidia are unusually 
asymmetrical and the long aedeagus is fused to the anellus. I know 
of no other phaloniid with such marked asymmetry in the male 
genitalia. 
Lasiothyris hemitephras, new species 
Figure 27; PuateE 3 (Fa. 1) 
Alar expanse 16-18 mm. 
Labial palpus ocherous white; second segment sparsely and minutely 
irrorate with fuscous. Antenna pale grayish fuscous; scape ocherous 
white. Head ocherous white; laterally and on crown, light buff. 
Thorax ocherous white; tegula buff anteriorly. Forewing ground color 
cinereous; from mid-dorsum to costal edge of cell, a transverse 
ochraceous-buff shade; apical third ochraceous buff, irregularly and 
sparsely spotted with cinereous; underside rather strongly infuscated; 
cilia cinereous with a dark gray basal line. Hindwing light grayish 
fuscous; cilia ocherous white with a gray subbasal line. Foreleg 
ocherous white marked with cinereous; midleg similar to foreleg; 
hindleg ocherous white. Abdomen pale grayish fuscous dorsally, 
ocherous white ventrally. 
Female genitalia slides JFGC no. 11222, 11717. Ostium wide, 
asymmetrical. Antrum not differentiated. Inception of ductus semi- 
nalis from left side of bursa copulatrix. Ductus bursae short, very 
broad, strongly sclerotized, with two longitudinal, folded ridges 
ventrally. Bursa copulatrix mostly membranous; accessory bursa 
