SUBFAMILY POLLENIINAE 357 
Melanodexia are apparently more glabrous and tend toward 
shining black, while species of Melanodextopsis have the ab- 
domen rather silvery pollinose and marmorate. 
The shape of the carina and details of the male genital seg- 
ments of Melanodexiopsis appear to be similar in many respects 
to those parts in species belonging to the Oriental genus Xantho- 
tryxus Aldrich. 
Genotype. Melanodexiopsis tristina, new species. 
Melanodexiopsis grandis (Shannon), new combination 
Melanodexia grandis Shannon, Wash. Ent. Soc. Proc. 28(6) :138, 
1926. (Type, male ort Monterey County, Calif., No. 
28894, U. 8S. National Museum.) 
Similar to tristina but middle tibia with ventral bristles and 
frontal row of bristles doubled. 
Male. Head (pl. 7, D) height 13.2; head width 14.2; eye 
height 9.5; bueea 0.39 eye height; length at antenna 8.5 and at 
vibrissa 8.2; parafaciale 2.8 in width opposite lunule; width 
between vibrissac 2.4; frontal bristles in two rows; front at 
narrowest 0.09 of head width, 0.20 at vertex and 0.50 at lunule; 
carina hardly apparent except between antennal bases; vibrissae 
high above oral margin; third antennal segment about 1.5 times 
as long as second; palpus 3.6; haustellum 0.5 head height. 
Thorax with two postacrostichal bristles. 
Legs with middle femur with three or four anterior bristles 
on middle third; middle tibia with two or three anterodorsal 
bristles apically, one ventral bristle at apical third, two posterior 
bristles, and one or two posterodorsal bristles. 
Genital segments (pl. 31, I and J) as illustrated. 
Female. Head height 12.5; head width 14.7; eye height 8.0; 
bueea 0.42 eye height; length at antenna 7.8 and at vibrissa 7.0; 
distance between vibrissae and width of parafaciale opposite 
lunule approximately equal (2.8:2.8). Otherwise as in male 
except for normal sexual differences. 
Length. 8-9 mm. 
One male (type), two males (paratypes) and one female (allo- 
type), from the type locality; one male, Pacific Grove, Calif. 
(May 4, 1906, Aldrich), and one male, Monterey, Calif. (July 
22, 1935, J. Russell), 
Melanodexiopsis idahoensis, new species 
| Similar to tristina but epistoma short and wide, the vibrissae 
only slightly above the oral margin. | 
Female. Head with epistoma short, nearly as wide as clypeus, 
