OF WASHINGTON, VOLUME XVIII, 1916 111 



along posterior margin of scutellum and on post-alar calli. Abdomen 

 bright metallic green; second segment with two opaque black cross-bands, 

 the first one on the anterior margin; third segment similarly ornamented, 

 but with the second opaque band very narrow; fourth segment entirely 

 metallic green, longer than broad. Femora of the front and middle legs 

 brownish black exteriorly, reddish brown on inner sides, yellow at bases 

 and tips; hind femora blackish on more than basal half, yellow distally. 

 All the tibiae and first three joints of tarsi yellow, the other tarsal joints 

 black. Length : Body about 15 mm. ; wing 10 mm. 



Female: Frons aeneous black, reddish brown above antennae, with very 

 narrow whitish pollinose stripes along eyes and with a flat surface, not 

 depressed. Legs as in male, except that hind femora are yellow at base; 

 hind tibiae, except at base, nearly as thick as femora. Scutellum with 

 almost entirely black pile. Length about 12 mm.; wing 11 mm. 



Kanaka Bay, San Juan Islands, Washington, one male, type, 

 May 31, 1906 (J. M. Aldrich); Ft. Wrangel, Alaska, one female 

 allotype (Wickham). 



Type: Cat. No. 20287 U. S. N. M. 



Caliprobola aldrichi, new species. 



Very similar to opacus but more robust, head obviously broader than 

 high; abdomen brilliant bronze, with the pile more golden. 



Female: Frons depressed, dull aeneous black, somewhat reddish above 

 antennae, with dark brown pile and very narrow whitish pollinose stripes 

 along eyes. Dorsum of thorax sub-shining black, with dark brown pile; 

 meso-pleurae with rather long golden pile; posterior margin of scutellum 

 and post-alar calli with yellow pile. Abdomen banded similarly to opacus. 

 Fore femora dark on outer side, yellow on inner side; middle femora al- 

 most entirely yellow; hind femora yellow, a dark band around the middle; 

 the rest of legs yellow, except the last two joints of all the tarsi. Wings 

 infuscated anteriorly, darkest along the veins. Length: Body about 12- 

 14 mm., wing 11-12 mm. 



Described from three females: Mt. Rainier, Washington, above 

 Longmires, 5000 ft,, Aug. 3, 1905 (J. M. Aldrich). 



Type: Cat. No. 20288 U. S. N. M. 



I have great pleasure in naming this species in honor of Pro- 

 fessor J. M. Aldrich, who very generously sent me certain new 

 species of Syrphidae in order that I might describe .them. 



Caliprobola sorosis Will. 



Williston described this species only from the male; characters 

 for the female follows: 



Female: Frons dull darkaeneous, yellowish above antennae, with whitish 

 pollinose stripes along the eyes and with short brownish yellow pile. 



