162 HYMENOPTERA. 



black about the bases of the antennae ; occiput with considerable yellow 

 pile, but usually with more of less black hair admixed ; cheeks dark. 

 Labrum with tubercle-like areas having their hind (proximal) margins 

 rather sharply rounded and summits considerably concaved, the region 

 between them, and above the shelf -like projection, deeply excavated ; 

 the shelf-like projection rather wide and prominent. Malar space dis- 

 tinctly shorter than its width at the apex ; less than one-sixth as long 

 as the eye. Clypeus for the most part very delicately punctate over 

 the disc. Each lateral ocellus about one-half as far from the supra- 

 orbital line as from the nearest eye. Flagellum of antennae about one 

 and four-fifths times as long as the scape ; third antennal segment 

 longer than the fifth, the fifth longer than the fourth. 



Thorax. — Dorsum clothed with yellow pile ; mesopleurse covered 

 with yellow pile to the bases of the legs ; metapleurae mostly clothed 

 with yellow ; sides of the median segment sometimes entirely dark and 

 sometimes clothed with light yellow pile, but usually with a mixture 

 of dark and light hairs. 



Abdomen. — Dorsum: segment one yellow; segment two covered 

 with yellow pile, except for black on its apical margin ; segment three 

 black, but sometimes with slight touches of yellow pile on the extreme 

 side margins; segments four, five and six entirely black. Venter 

 black. Hypopygium without a median carina. 



Wings. — Rather dark brown ; the fore pair darkest in the region 

 beyond the veins. 



Legs. — Coxae and trochanters mostly dark ; femora with more or 

 less yellow pile on their lower sides ; fore and middle tibiae and corbi- 

 cular fringes dark. 



Worker. — Much like the queen, but the apical margin of the second 

 dorsal abdominal segment often covered with yellow pile and at least 

 the basal middle reddish tawny, pile of this color sometimes covering 

 the entire segment ; segments three and four usually with strong 

 touches of yellow pile on their extreme side margins ; the sides of the 

 median segment usually with pure, or nearly pure, pale yellow pile; 

 the face, above the bases of the antennae, and the occiput usually with 

 purer yellow pile than in the case of the queen. 



Male. — Head. — Face and occiput mostly covered with whitish pile ; 

 cheeks with some whitish pile connecting with that on the occiput. 

 Malar space about one-third as long as wide. Clypeus mostly covered 

 up with whitish pile. Ocelli in the narrowest part of the vertex, the 

 lateral ones separated by about one-half their own diameter from the 

 margins of the eyes. Third and fifth antennal segments equal in 

 length, the fourth much shorter than either ; flagellum about two and 

 three-fourths times as long as the scape. 



Thorax. — Dorsum, pleurae and sides of the median segment covered 

 with whitish pile. 



