MANUAL OF NATURAL HISTOEY. 231 



not prolonged into a beak ; abdomen oval, 

 broadest in middle or clavate, peduncled ; 

 fore-tibiae with a dilated spur. Usually bur- 

 row in old wood, and occasionally in sandy 

 places. 



III. TRIBE. FOLDED-WINGED HYMENOPTERA 

 (Diploptera). 



Fore-wings folded on themselves. Larvae, in the 

 social species, separately enclosed in cells. 



21. FAMILY. Solitary- Wasps (Eumenidae). An- 



tennae of males curved at tips; eyes notched; 

 mandibles elongate, produced ; labium di- 

 vided into four pilose setee ending in glands ; 

 wings folded when at rest ; abdomen con- 

 tracted, with a long narrow peduncle ; legs 

 not ciliated or spinose. Solitary. Males and 

 females only. Form cells of sand and clay. 



22. FAMILY. Social - Wasps (Vespidae). Antennae 



of males not hooked or recurved at tip ; eyes 

 notched ; mandibles as broad as long, trun- 

 cate at end ; wings folded when at rest ; ab- 

 domen rarely contracted into a peduncle ; 

 hind-tibiae with two spurs. Social. Males, 

 females, and neuters. Form cells of paper 

 arranged in tiers. 



IV. TRIBE. HONEY-GATHERING HYMENOPTEEA 



(Mellifera). 



Basal joint of hind-tarsi dilated, provided with 

 instruments for collecting and carrying pollen; larvae 

 living on honey. 



