50 Psyche [April 



like face, with mostly whitish hairs; antennae with rather long first joint, the 

 third wide, all black. Dorsum of thorax moderately shining, with two brown 

 lines in front, in the middle brown, back of the middle a little coppery on both 

 sides; humeral bristles one or two, scutellar one pair; a bimch of long, whitish 

 hairs behind humerus and above the notopleural suture, plem-ae densely whitish 

 pruinose, not shining, with conspicuous whitish hairs on propleura and hypopleura, 

 the propleural bristle however black; halteres yellow with brownish base of stalk. 

 Coxfe all with yellowish-white hairs and no black ones even at tip of front coxae; 

 femora rather opaque, with slight greenish metallic color, tibiae and tarsi gradu- 

 ally a little darker; fore femur with numerous short, stiff spines below, arranged 

 very indistinctly in two uneven rows; fore tibia on inner side with a row of short 

 spines, the last two or three at tip becoming erect and slightly longer; the tibia 

 itself is provided with a slight process at tip, turning toward the femur, on which 

 the longest spine stands; fore tarsus fully double the tibia, pulvdlli brownish. 

 Wings smoky, costa wholly blackish, an indistinct brown cloud on the hind 

 crossvein and another beyond it on the fourth vein. Abdomen rather shining 

 green, with black hairs above and whitish ones on the sides, the latter rather 

 conspicuous; hypopygium embedded, not very conspicuous. Length, 4 mm.; of 

 wing 4.3. 



Female. Length 5 to 6.1 mm.; of wing 5.6 to 6 mm.; otherwise like the male. 



Seventeen specimens, both sexes: Moscow, Idaho (type); 

 Pulhnan, Seattle and Friday Harbor, Wash., dated July 19 and 

 Aug. 2 and 16; Palo Alto and Redwood City, Cal., dated March 

 1 and April 12, 19 and 25. Three of the Washington specimens 

 are from Professor INIelander, while one from Palo Alto is from 

 the collection of Stanford University. 



Another male from Moscow differs in nothing but its minute 

 size, 3.1 mm. 



Hydrophorus plumbeus sp. nov. 



Female. Wholly covered with dense plumbeous pruinosity, nowhere showing 

 any metallic color. Occiput with a transverse row of black bristles including the 

 postverticals, which are continuous with the infra-orbitals extending entirely to 

 the mouth; the upper orbitals do not quite connect with this series, so there are 

 half a dozen small black bristles on the upper orbit which are a little isolated from 

 the ones on the orbit below; no black spines under the neck; front plumbeous, 

 yet in oblique view rather blackish, not shining; face very wide, uniformly plumb- 

 eous, the palpi concolorous, in the described specimen opened out so that the 

 base of the proboscis shows between — probably not the usual position; antennae 

 of moderate length, rather slender, the third joint truncated, arista short, its penul- 

 timate joint over half as long as the ultimate, which is hardly tapering at all except 

 at the extreme tip, but ends in a very fine point. Thorax ever;ywhere plumbeous, 

 but with two fine dark lines running back from the front edge in the middle; humeri 

 each with three or four bristles of various sizes; on the mesial side of the humerus 

 a group of bristles, and another behind the humerus and above the notopleural 



