HYMENOPTERA 891 



The Cuckoo-wasps, p. 934 Family Chrysidid^e 



The Anthoboscids. p. 935 Family ANXHOBOSCiDiE 



The Sapygids. p. 935 Family SAPYGiDiE 



The Thynnids. p. 935 Family Thynnid^ 



The Tiphiids. p. 936 Family TlPHllD^ 



The Velvet-ants. p. 936 Family Mutillid^ 



The Scoliids. p. 937 Family Scoliid^ 



The Ants. p. 937 Family Formicid^ 



The Bethylids. p. 948 Family Bethylid^ 



The Rhopalosomids. p. 948 Family Rhopalosomid^ 



The Typical Wasps or Diploptera. p. 948 Family Vespid.^ 



Superfamily Sphecoidea. The wSphecoid-wasp and the Bees. 



I. The Sphecoid-Wasps. 



The Ampulicids. p. 961 Family Ampulicid^ 



The Dryinids. p. 961 Family Dryinid^ 



The Typical Sphecoid- wasps, p. 962 Family Sphecid^e 



II. The Bees. p. 972 



The Bifid-tongued Bees. p. 976 Family Prosopid^e 



The Andrenids. p. 978 Family ANDRENlDiE 



The Leaf-cutter Bees and their Allies, p. 982 Family Megachilid^ 



The Bumblebees, p. 984 Family Bombid^ 



The Honey-bees. p. 988 Family Apid^e 



KEY TO THE SUBORDERS OF THE HYMENOPTERA 



A. Base of the abdomen not slender but broadly joined to the thorax. 



B. Antennffi inserted between the eyes above the base of the clypeus with the 

 bases of the antennae exposed; front wings with the transverse part of vein 

 M2 present or if wanting {Hylotoma) then vein R4 is present in the hind 

 wings, which therefore have a closed submarginal cell; ovipositor either 

 sawlike or a sturdy borer, never threadlike or capable of being coiled within 



the body. p. 891 Chalastogastra 



BB. Antennas inserted below the eyes immediately above the mandibles under 

 a transverse ridge, their bases concealed; front wings with the transverse 

 part of vein M2 wanting; vein R4 in the hind wings wanting, therefore no 

 closed submarginal cells; ovipositor threadlike and coiled within the meso- 

 thorax. p. 993 Idiogastra 



AA. Base of the abdomen constricted into a narrow pedicel, p. 905. Clistogastra 



Suborder CHALASTOGASTRA or SYMPHYTA* 

 The Sawfiies and Horn-tails 



This suborder includes the more generahzed members of the 

 Hymenoptera, those in which the form of the body is less modified 

 and the venation of the wings less reduced than is the case with other 

 members of the order. 



The basal segments of the abdomen are similar in form and the 

 abdomen is broadly joined to the thorax as in the more generalized 

 orders of insects. The first abdominal segment is not closely anchy- 

 losed to the thorax, forming a propodeum, as is the case in the Clisto- 

 gastra, and its tergum is usually longitudinally divided on its middle 

 line. 



*The name Chalastogastra is the one most commonly applied to this sub- 

 order and for that reason is used in this work; but some authors use Symphyta, 

 which is really the older name. The etymology of these names is as follows: — 



Chalastogastra; chalastos (j^aXacrris), loose; gaster (■yaffT'flp) , the belly. 



Symphyta: sym (ff'uv) with; phyton ((pvrdv), plant. 



