396 AMERICAN HYMENOPTERA. 



punctate on the disc, the central apical portion being impunctate, 

 smooth and shining ; fifth antennal segment nearly as long as the 

 third and fourth taken together, third distinctly though not greatly 

 longer than fourth. 



Thorax. — Coloration much as in females, but with the yellow pile 

 on the anterior part of the thorax extending down on the front sides 

 of the pleura, in a narrowing strip to, or nearly to, the bases of the mid- 

 dle legs ; posterior part of the mesopleura and the metapleura covered 

 with dark pile. 



Abdomen. — Dorsum covered with black pile, except segments four 

 and five, these being covered with yellow pile. Venter bearing black 

 pile for most part, but with the yellow of dorsal segments four and five 

 extending onto the extreme sides of the corresponding ventral segments 

 and onto the extreme sides of the posterior margin of segment three ; 

 apical segment with a prominent transverse carina a little in front of 

 its hind margin, the area between this carina and the margin bearing 

 short ferruginous hair. 



Genitalia. — {Y\%^. 78 and 102). Apical portion of inner spatha 

 quadrangular ; heads of sagittse short and with apices so strongly re- 

 curved as to appear like hollowed out shells. 



Wings. — Not very deeply stained with brown, considerably lighter 

 than those of queen. 



Legs. — Fore coxae black ; middle and hind coxae mostly black, but 

 usually with some yellow hairs on their outer sides ; trochanters mostly 

 black, sometimes with a very faint sprinkling of yellow ; femora, fore 

 and middle tibiae and outer sides of hind tibiae black. 



Dimensions. — Length: queen, 15 mm. to 22 mm. ; worker, 9 mm. 

 to 15 mm. ; male, 12 mm. to 16 mm. Spread of wings: queen, 37 

 mm. to 44 mm. ; worker, 24 mm. to 31 mm. ; male, 26 mm. to 35 

 mm. Width of abdomen at second segment : queen, 9 mm. to 11 

 mm. ; worker, 5^ to 9 mm. ; male, 5^ mm. to 1\ mm. 



Redescribed from numerous queens, eight workers and 

 four males (one of them a homotype). 



Variation. — The above described forms comprise the typi- 

 cal californicus and they are the forms most frequently found 

 in collections. The species is, however, a very variable one 

 and the typical forms are really a part of a line of color varia- 

 tions from dark to light. I have seen almost every conceiv- 

 able variation connecting the following female and male 

 forms in order : 



Color Variant 1. — Queen like typical californicus, but with abdomen 

 entirely black. One specimen from Prince Albert, Saskatchewan. 



Color Variant 2. — Worker like typical californicus, but with fourth 



