158 NEW YORK STATE MUSEUM 



joined to the middle of subcosta by a straight, parallel crossvein 

 and uniting with the margin at the apex; the fifth joins the posterior 

 margin at the distal fourth, the sixth near the basal half. The 

 claws are slender, short and the pulvilli large and broad. The type 

 species, Cecidomyia longicollis H. Lw., was fixed by 

 Karsch, though seven years earlier Rondani designated C. pec- 

 t o r a 1 i s Winn, as the type. The latter, however, was not before 

 Loew, when the genus was erected, and is not even congeneric. 

 Later Kieffer cites this species as the type and then in 1897 mentions 

 A, longicauda H. Lw., as the typical form. The type species, 

 namely, A. longicollis H. Lw., has 24 sessile segments in the 

 female, the male having 21 segments, the stem of the flagellate 

 segments being three-fourths the length of the basal enlargement. 

 Kieffer states that the male genitalia has the claw large and club- 

 shaped. 



Key to species 

 a 16 antennal segments 



b Fifth antennal segment with a stem three-fourths the length of the basal 



enlargement nobilis Felt, C. 1464 



bb Fifth antennal segment with a stem one-half longer than the basal enlarge- 

 ment 

 c Abdomen yellowish brown, length 2 mm, the basal enlargement of the 

 fifth antennal segment with a length three times its diameter, the 



terminal clasp segment broadly triangular f u r c a t a Felt, C. 336 



bbb Fifth antennal segment with a stem two and one-half times the length of 

 the basal enlargement 

 c Abdomen yellowish brown, length 2.75 mm, basal enlargement of fifth 

 antennal segment with a length one-half greater than its diameter, 



terminal clasp segment with a spur at the apical fourth 



a p i c a 1 i s Felt, C. 1492 



cc Abdomen fuscous yellowish, length 2.5 mm, basal enlargement of the 



fifth antennal segment with a length twice its diameter, terminal 



clasp segment with a spur near the basal half, .media n a Felt, C. 1 405 



aa 17 or 18 antennal segments, the fifth with a stem about three-fourths the 



length of the basal enlargement 



b Abdomen light yellow, length 2 mm, the basal enlargement oi the fifth 



antennal segment with a length three-fourths greater than its diameter 



flavida Felt, C. 504 



bb Abdomen fuscous yellowish, length 1.5 mm, the basal enlargement o( this 



fifth antennal segment with a length one-fourth greater than its diameter 



u m b r a Felt, C. [499 



(Kid [9 antennal segments 



b Fifth antennal segment with a stem in the male l luve fourt lis, and in the 



female one-fifth, the length of the basal enlargemenl 

 c Abdomen reddish orange, length, male, 2 mm, female 1.5 mm, the basal 

 enlargement of the tilth (male) antenna! segment with a length twice 



its diameter. Reared from Rhabdophaga batatas gall on willow 



s a 1 1 e 1 p e r d a Felt, C. ai8i5a 



