4 Harry Scott Smith 
den under the clypeus; anterior ocellus nor- — 
mal, lateral ocelli sometimes more or less dis- 
tofted’ $.a..smerekaone yas te dm LARRIDAE ~ 
EE. Marginal cell not appendiculate; transverse median. — 
nervure sometimes sinuate; mandibles entire 
on their exterior margin; labrum large, well 
developed and triangularly elongated, much ~ 
longer than wide; ocelli more or less imper- 
FECES co cktaa pues tunics aed BEMBICIDAE 
DD. Abdomen petiolate, or subpetiolate; transverse median — 
nervure not sinuate; ocelli distinct; labrum gen- 
erally > hidden .277 5 ats idne e PEMPHREDONIDAE 
BB. Front wings with only one cubital cell; median cell in hind wings 
fully twice as long as submedian. 
C. Front wings with the first cubital cell distinct, not confluent 
with the first discoidal cell; scutellum and postscutellum 
normal, without squamae or spines; eyes diverging to- 
ward vertex; temples very broad....CRABRONIDAE 
CC. Front wings with the first cubital cell confluent with the 
first discoidal cell; scutellum margined or with — 
squamae; postscutellum with a stout spine or forked 
process; eyes converging toward vertex; temples com- 
patatively narrow. os es oes sake sees OXYBELIDAE 
Family SPHECIDAE 
KEY TO THE SUBFAMILIES 
Second cubital cell receiving both recurrent nervures, or the second re- 
current nervure is interstitial with the second transverse cubitus, al- 
though sometimes the first recurrent is interstitial with the first trans- 
verse cubitus, or then received by the first cubital cell. 
Claws with a single tooth beneath, although sometimes very minute; 
more rarely without a tooth, the claws simple; tarsal comb in the 
female absent; abdomen always with a one-segmented petiole; cubital 
nervure of hind wings interstitial or nearly so; metathorax with a 
large U-shaped area above.............2-000.- SCELIPHRONINAE 
Claws simple, without a tooth beneath; tibiae more or less spinous; tar- 
sal comb in female present; abdomen most frequently very elongate, 
the petiole composed of two segments, rarely of only one segment; 
cubital nervure of hind wings usually originating beyond the trans- 
Verse. median. nNervaire-se saiiuass.. terete eee ee SPHECINAE 
Second cubital cell receiving only the first recurrent nervure; the second — 
recurrent nervure received by the third cubital cell, or at least beyond 
the second transverse cubital; claws with one to six teeth beneath; 
326 
