SOLITARY WASPS. 



truncate; back of abdomen flattened. Astatinae. For 

 the most part, they are less than .5 in. long. Astata uni- 

 color (abdomen black) and bicolor (abdomen red) are 

 common species. 



2. Hind ocelli perfect ; inner margins of eyes nearly parallel ; 

 pronotum trilobed. Lyroda triloba (wings dark all over) 

 and subita (wings dark at tips). Larval food, Nemobius. 



Hind ocelli imperfect, flattened; inner margins of 

 eyes converging above; pronotum simple 3. 



3. Front of head strongly raised so that there is a trans- 

 verse ridge below front ocellus; mandibles toothed (in 

 Larra there are no teeth) ; hind ocelli narrow ; tip of abdo- 

 men with silver pile. Notogonidea argentata; larval food, 

 immature crickets. 



Front not strongly raised 4. 



4. Hind ("side") ocelli oval or elongate-oval in outline; 

 front not raised along inner margins of eyes ; tip of abdomen 

 without pile. Tachysphex. There are a number of species 

 of these sand-loving wasps. 



Hind ocelli larger dorsally so that they appear 

 hooked 5. 



5. Front slightly raised along inner margins of eyes; 

 pygidium without pile. Larropsis distincta. 



Front not raised along inner margins of eyes ; pygidium 

 clothed with pile. Tachytes of which we have numerous 

 species, all probably nesting in sand and stocking their 

 nests with grasshoppers. 



BEMBECID.E 



All of this family nest in the ground. Bicyrtes seems 

 to prefer Hemiptera as larval food and, after stocking the 

 nest, seals it up. The other species, mentioned here, use 

 flies and, unlike most solitary wasps, feed their larvae from 

 day to day. Sometimes a large number of individuals 

 nest close to each other. 



i. Mandibles simple. Microbembex, monodonta being 

 the specific name usually given to all from the Northeast; 

 black with greenish-white markings. 



Mandibles having a tooth within 2. 



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