50 ILLINOIS BIOLOGICAL MONOGRAPHS [368 



The Emphytinae is a large subfamily embracing a number of genera 

 and numerous species. MacGillivray considers this the second subfamily 

 of his generalized Tenthredinidae and places it between the Diprioninae 

 and Selandriinae. The larvae of this subfamily are found readily and in 

 general appearance and habitus resemble very closely the larvae of the 

 Selandriinae and Tenthredininae, but they can be separated by the number 

 of annulets, which in this subfamily, with the exception of Hemitaxonus 

 and Epitaxonus, is six, while in the other two subfamilies it is seven. The 

 two genera mentioned are characterized by the presence of seven annulets 

 on the typical abdominal segment and also by the setiferous larvapods, 

 thus resembling in these two particulars the larvae of the Selandriinae. 

 It is of interest to note that Rohwer would associate Hemitaxonus with 

 :;uch genera as Selandria, Eriocampoides, etc., in the tribe Selandriini of 

 his subfamily Selandriinae. Middleton (1915) has published a definition 

 of the genus Dimorphopteryx together with a key for the separation of 

 three species. 



The writer has collected a large number of larvae belonging to this 

 subfamily, but on account of the difiSculty of breeding adults many 

 species remain unidentified. In the preparation of the synoptic key to the 

 genera and in discussions following, only bred or otherwise identified 

 species have been considered, the consequence being that future study may 

 require much modification in our conception of the various genera dealt 

 with. 



GENERA OF EMPHYTINAE 



1(4) Third abdominal segment with 7 annulets; larvapods setiferous 2. 



2(3) Larvapods with 5-3-1 setae on cephalic, lateral, and caudal aspects respectively; 

 thoracic legs with femur longer than or subequal to tibia; labial palpi with segment 



2 longer than segment 1 ; maxUlar>' palpi with segments subequal in length 



Hemitaxonus Ashmead. 



3(2) Larvapods with 8-5-1 setae on cephalic, lateral, and caudal aspects respectively; 

 thoracic legs with femur shorter than tibia; labial palpi with segments subequal to 



each other in length; maxillary palpi with segment 2 longer than segment 1 



Epitaxonus MacGillivray. 



4(1) Third abdominal segment with 6 annulets; larvapods glabrous 5. 



5(26) Tenth abdominal tergum and prothoracic and mesothoracic tergites without con- 

 spicuous fleshy pointed protuberances; thoracic legs normal in form, with trochanters 

 distinct 6. 



6(9) Annulets 1, 2, and 4 setiferous 7. 



7(8) Antennae with segment 5 longest; legs with femur longer than tibia; head usuall}' 

 without markings; labial palpi, if segments not subequal, segment 2 longer than 

 segment 1 Empria Lepeletier. 



8(7) Antennae with segment 1 longest; legs with femur subequal to tibia; head usuallj' 

 with markings; labial palpi, if segments not subequal, segment 2 shorter than seg- 

 ment 1 Parataxonus MacGUlivray 



9(6) Annulets 2 and 4 setiferous 10. 



