182 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



antennae the same, but was confused by a specimen of doubt- 

 ful authenticity having 16-jointed antennae. The generic posi- 

 tion of A. rupee, is shown to be the same as that of A. brassicce 

 and T. picens, so that there seems to be no reason to doubt 

 that the description by Curtis is of the same species as those 

 by Cresson and Marshall. 



Cresson placed this species in the genus Trioxys Hal., 

 Ashmead in the genus Lipolexis Foerst., and Marshall called 

 it an Aphidins Nees. In the opinion of the writer it belongs 

 in the genus Diceretus Foerst. It lacks the horns on the tip 

 of the abdomen typical of Trioxys and possesses a very dis- 

 tinct second discoidal cell, a character absent in Lipolexis ^ 

 but present in Durrctns, according to the best interpretation 

 of Foerster's table of genera. Marshall did not recognize any 

 of the Foersterian genera, grouping them all under Aphidins. 

 The species should therefore be known as Di&rctus rapcc 

 Curt. 



Diseretus salicaphis Fitch. 



Trioxys salicaphis Fitch, 1st and 2nd Kept. Ins. N. Y., 1856, 



p. 137. 

 Lipolexis salicaphidis Ashmead, Proc. U. S. Nat. Mus., 1888, 



p. 671. 



Trioxys salicaphis, Fitch was described from New York and 

 Lipolexis salicaphidis Ashm. from California. Ashmead 

 states in his description of salicaphidis that this species can 

 not be the Trioxys salicaphis Fitch on account of the number 

 of autennal joints. Fortunately the types of both species are 

 available for comparison. Fitch gave the number of antenual 

 joints for his species as 13 without specifying the sex. 



Ashmead described the female of his species as having 15- 

 jointed and the male as having 16-jointed antenna?. Among 

 Ashmead's types are males with 15-jointed and 16-jointed and 

 one female with 13-joiuted antennae. I could find no females 

 with 15-jointed antennae, and am forced to conclude that Dr. 

 Ashmead mistook a male for a female. In every other respect 

 the types of Fitch and Ashmead are alike and I believe repre- 

 sent the same species. 



With this species, as with Diceretiis rapt?, the second 

 discoidal cell is present and complete, placing it in the genus 

 Di&retus Foerst. instead oiLipo/cxis Foerst. as Dr. Ashmead 

 placed it. The parasite of the grape aphis which Dr. Ashmead 

 determined as Lysiphlebus salicaphis Fitch (Proc. U. S. Nat. 

 Mus., 1888, page 669) is possibly an undescribed species of 

 Lysiphlebus. 



