10 HYMENOPTERA CHAP. 



Four primary divisions of Aculeates are generally recognised, 

 viz. Anthophila (Bees), Diploptera (Wasps), Fossores (Solitary 

 Wasps), Heterogyna (Ants). Though apparently they are natural, 

 it is impossible to define them by characters that are without 

 some exceptions, especially in the case of the males. Ashmead 

 has recently proposed l to divide the Fossores ; thus making five 

 divisions as follows : 



Body with more or less of the hairs on it plumose . 1. Anthophila. 



Hairs of body not plumose. 



Pronotum not reaching back to tegulae . 2. Entomophila 



[ = Fossores part] 

 Pronotum reaching back to tegulae. 



Petiole (articulating segment of abdomen) simple without scales or 



nodes. 

 Front wings in repose with a fold making them narrow 



3. Diploptera. 



Front wings not folded . . 4. Fossores [part]. 



Petiole with a scale or node (an irregular elevation on the upper side) 



5. Heterogyna. 



We shall here follow the usual method of treating all the 

 fossorial wasps as forming a single group, uniting Ashmead's 

 Entomophila and Fossores, as we think their separation is only 

 valid for the purposes of a table ; the Pompilidae placed by the 

 American savant in Fossores being as much allied to Entomo- 

 phila as they are to the other Fossores with which Ashmead 

 associates them. 



Division I. Anthophila or Apidae Bees. 



Some of the hairs of the body plumose, ; parts of the mouth don- 

 gated, sometimes to a great extent, so as to form a protrusible 

 apparatus, usually tubular with a very flexible tip. Bnxl 

 joint of hind foot elongate. No wingless adult forms ; in 

 some cases societies are formed, and then barren females called 

 workers exist in great numnrrs, and- carry on the industrial 

 operations of the community. Food always derived from the 

 vegetable kingdom, or from other Bees. 



There are about 150 genera and 1500 species of bees at 

 present known. Some call the division Mellifera instead of 

 Anthophila. The term Apidae is used by some authorities to de- 

 note all the bees, while others limit this term to one of the families 

 1 Proc. cnt. Soc. Washington, iii. 1896, p. 334. 



