124 GENERA OF HYMENOPTERA. 



latter genus, found in Nevada and Calif'oi-nia, is quite small in com- 

 parison with the generally large, fine species of Masaris, of which 

 seven have been descril)e(l from Texas, Coloi-ado and California. 

 The geographical distribution of the species of this genus is remark- 

 able, the only other two representatives known Ix'ing found in North 

 Africa. Nothing is as yet known regarding their habits. 



The following characters will sufficiently separate the genera : 



Table of Genera. 



Anleiior wings with two complete submarginal cells, the second submarginal re- 

 ceiving both recurrent nervures; antenuiv of "^ lonu and knobbed at tip, 

 that of 9 short and clavate Ma«*ari?s Fabr. 



Anterior wings with three complete suhniarjjinal cells, the second and lliiid siib- 

 marginals each receiving a recurrent nervure ; antenna; rather short and 

 clavate in both sexes ICiipara^ia Cress. 



Family EUMENIDiE. 



In this family, comprising the Solitary Was})S, the antenna- are 

 filiform or nearly so, and often terminated by a hook in the S ; the 

 intermediate tibite have but one a])ieal spin- and the tarsal claws are 

 uiiidentatc!. The genera with sessile or subsessile abdomen are closely 

 allied, the only characters, so far discovered, by which they can be 

 separated, are those found in the structure of the mouth-parts, which 

 unfortunately are often concealed ; there are, however, certain supei- 

 ficial difiereuces of form and facies, impossible to describe intelli- 

 gently, but which enable a practiced eye to distinguish the genera 

 witiiout recourse to an examination of the troplii. 



The genera and species of this family, including also the Masarida?, 

 have been elaborately nionogra])hed by Dr. de Saussure, in his ad- 

 mirable " Synopsis of American Wasps," i)ul)lished in 1875 by the 

 Smith.^onian In.stitution, and which will be found to be itidispensible 

 to those desiring to study this interesting and beautiful liimip of' in- 

 sects. 



The following table is about the best that can be otlered at present 

 for the separation (if the g(>nera : 



Table of Genera. 



.Vbdomen ])etiolate. 



Head large, quadrate, much e.xjianded b('hin<i tlie eyes, making the (dieeks 



broad; (dyjieus broader than long XotliiiM Fabr. 



II<a<l transverse, not expanded behind the eyes, which almost entirely cover 



tiie checks ; clypeus longer than broad ICllllK'llOX l.utr. 



