March, I9II.] FeLT : GENERIC SYNOPSIS OF ItONID.^. 53 



Kieff. by the lobes of the ventral plate being short and broadly 

 rounded; the ovipositor is short, the pulvilli a1)out half the length of 

 the claws. Africa. 



Genus YOUNGOMYIA Felt 1908, type Dicrodiplosis podophyllw Felt. 



Readily separated from the four preceding and the three follow- 

 ing genera by the slender terminal clasp segment being distinctly 

 longer than the basal clasp segment. The flagellate antennal seg- 

 ments of the male are trinodose, the dorsal plate is almost divided 

 and the ventral plate roundly truncate. North America. 



Genus DICRODIPLOSIS Kieff. 1895, type D. fascia fa Kieff. 

 The type species has the ovipositor short, the lobes with the mar- 

 gin pectinate. The American species provisionally referred to this 

 genus have the ventral plate usually long. Europe, North America. 



Genus DICHODIPLOSIS Riibs. 1910, type D. langaii Riibs. 

 Distinguished from the preceding by the greatly produced oviposi- 

 tor; ventral plate narrow, not elongate, rounded apically, the claws 

 bent at nearly right angles, the tooth scarcely noticeable and nearly 

 parallel with the main part of the claw. Europe. 



Genus THOMASIA Riibs. 1910, type Clinodiplosis oculipevda Riibs. 



Separated from the preceding genus by the deeply emarginate, not 

 prolonged ventral plate, the tooth of the claws strong and erect. 

 Europe. 



Genus BREMIA Rond. i860, type Diplosis dccorata H. Lw. 

 Distinguished from the preceding genera by the anterior claws 

 being toothed, the posterior simple and easily separated from most 

 of the other Itonidinarise by the greatly produced setae and loops of 

 the circumfili on the ventral portion of the flagellate antennal seg- 

 ments. Easily separated from the following genus by the rudimentary 

 middle circumfilum, the flagellate segments apparently with but two 

 circumfili. Europe, North America. 



Genus APHIDOLETES Kieff. 1904, type A. abietis Kieff. by present designation. 

 Easily distinguished from the preceding form by the three well- 

 developed circumfili on the flagellate antennal seginents of the male. 

 Europe, North America, Australia. 



