NO. 1206. ICHNEUMON FLIES— ASHMEAD. 5 



Up to the present time no general work on the group has 1)een pul)- 

 li.shed, and thi.s contri]>ution is the fir.st effort made to classify the 

 group as a whole or to l)ring together in s^'.stematic order, or in talju- 

 lar form, the families, subfamilies, tribes, and the described genera of 

 the world. 



The author, although familiar with all of the groups and with most 

 of the genera, has in some cases been compelled to rely upon descrip- 

 tions for placing certain of the genera. The work, therefore, must ])e 

 imperfect in some particulars, l)ut he hopes for it a kindl}- reception, 

 and trusts it will not only stimulate the collecting of these important 

 insects, but that it will afford an aid and a guide for future study. 



The families recognized may be distinguished hj the use of the fol- 

 lowing table: 



TABLE OF FAMILIES. 



"Wingless forms 7 



Winged forms 2 



2. Costal and subcostal veins confluent, extending close together, side by side, 



the costal cell therefore absent 3 



Costal and subcostal veins separated, a space between, the costal cell therefore 

 present, distinct. 



Abdomen inserted normally, sessile or subsessile, or the first segment 

 long, petioliforni; front wings with only one recurrent ner^•^lre; head 

 most frequently globose and usually tuberculous 6 



Abdomen petiolated, inserted upon the dorsum of the metathorax, the 

 body of same usually strongly compressed; front wings with one or 

 two recurrent nervures, more rarely with none; head variable l)ut 

 never globose nor tuberculous; antennse 13-14 jointed, inserted either 

 just above the clypeus or far above it on the middle of the face. 



Family LXXIV. Evaxiid.e. 



3. Front wings with iico recurrent nervures (the second recurrent absent only 



in the genus Pharsalin Cresson) 4 



Front wings with only one recurrent nervure or with none 5 



4. First cubital and first discoidal cells always confluent; abdominal segments 



2-3 usually flexible, rarely connate; mandibles attached normally. 

 Ventral abdominal segments hard and chitinous, without a fold; dorsal 

 segments 2 and 3 connate, not flexi1)le; scutellum spined. 



Family LXXV. Agriotvpid^. 

 Ventral a]:>dominal segments soft and meiBbranous, usually with a fold; 

 dorsal segments 2 and 3 flexible; scutellum rarely spined. 



Family LXXVI. IrnxErMoxiD.E. 

 First cubital and first discoidal cells separated, distinct, not confluent; man- 

 dibles attached abnormally, the tips turned outwardly and not meet- 

 ing when closed Family LXXVII. Alysiid.e. 



5. ^Mandibles attached abnormally, the tips turned outwardly, not meeting when 



closed Family LXXVII. Alvsiid.k. 



Mandibles attached normally. 



Abdominal segments 2 and 3 most frequently rigid, connate, not flexil)le; 

 if not rigid, then all the segments are flexible; abdomen never greatly 

 elongate and strongly compressed; flrst cubital and first discoidal 

 cells, although not always, most frequently distinct and sepai'ated. 



Familv LXXVIII. Bkaconidje. 



