WASP GENUS CERCERIS — SCULLEN 353 



Group II 



1. Tergum 2 black or with more or less ferruginous 2 



Tergum 2 all yellow or with a broad yellow band 3 



2. Terga 1 and 2 black, basal half of terguna 3 black; posterior half of tergum 



3 and reiBaining posterior terga brownish yellow (Arizona, New Mexico, 



and southern Texas) dilatata dilatata Spinola 



Black of basal abdominal segments more or less replaced with red (Big Bend 

 National Park and Davis Mts. in Texas, southern New Mexico, and 

 southern Arizona) dilatata chisosensis ScuUen 



3. All terga of the abdomen yellow or very light fulvous except for a trace of 



emargination at the base 4 



Bands on terga 3 to 6 deeply emarginate anteriorly in middle 6 



4. Thorax black to dark fuscous background; first abdominal segment may show 



more or less red californica californica Cresson (in part) 



Thoracic background fulvous 5 



5. About 10 mm. in length; enclosure lightly ridged (southern California and 



adjoining areas californica arno Banks 



About 14 mm. in length; enclosure relatively smooth but with a few pits 

 in the lateral angles (southern California and adjoining areas) . 



grandis grandis Banks 



6. Length about 10 mm.; legs amber and yellow (this species shows great varia- 



tion in amounts and shades of yellow and red throughout its range west 

 of the Rocky Mountains from British Columbia to Texas). 



californica californica Cresson (in part) 



Length about 12 to 15 mm.; legs black and yellow; emarginations on terga 



usually narrow but deep, that on tergum 2 with a tendency to be enclosed 



by yellow (California and southwestern Oregon) . . . completa Banks 



Group III 



1. Broad bands with little or no emargination on terga 3 to 6 2 



Bands on terga 3 to 6 either greatly reduced or with deep emarginations . 3 



2. Background black or dark fuscous (southern California). 



sandiegensis Scullen 

 Backgound ferruginous (southern Arizona and adjoining areas). 



cochisi Scullen 



3. Black with yellow and/or fulvous markings, no red or ferruginous ... 5 

 Black with red and/or ferruginous markings (Florida and adjoining areas) . 4 



4. Marginal extension of the clypeus about as wide as half the length of the 



epistomal suture; mandibular denticles strong; enclosure smooth. 



flavofasciata floridensis Banks 

 Marginal extension of the clypeus about equal in width to the length of the 

 epistomal suture; mandibular denticles small; enclosure ridged. 



rufopicta F. Smith* 



5. Lower part of the clypeus showing considerable black and the yellow area 



of the medial lobe tapering apically to an acute point; metanotum yellow 

 (common through the Eastern States from southern Minnesota, southern 

 Wisconsin, southern Michigan, and New England south to the Gulf of Mex- 

 ico and west to Utah and the Southwest) . compacta conipacta Cresson 



8 Field observations may prove C. rufopicta F. Smith to be the male of C. 

 robertsonii emmiltosus Scullen or C. roJtertsonii miltosus Scullen. 



