OF WASHINGTON, VOLUME XII, bill). 181 



fact that all the progeny in this case were males at least sug- 

 gests the same mode of reproduction in this species. In other 

 experiments in which females with 14-jointed antenna? were 

 used both males and females were represented in the progeny. 

 Among the specimens thus reared from females having 14- 

 jointed antennae were found male specimens having 16- and 

 others having 17-jointed antennas; also females having 14 and 

 others with 15 joints. One male specimen had apparently 

 only 15 joints and one female apparently but 13 joints, the 

 last joint of the antenna? in each case being very indistinctly 

 divided. No males with 18 joints were reared, but as the 

 number of reared specimens was not large, it does not prove 

 that the individuals having that number in the original lot of 

 328 were wrongly considered as belonging to this species. A 

 larger series would no doubt contain such individuals. 



Curtis, in 1855, described and figured a European parasite 

 of Aphi* hrassicce under the name of 7'riouvx rapce ^ but 

 afterwards placed it in the genus Aphidins. In a somewhat 

 meager description, apparently of a female (his figure rep- 

 resents that sex) he stated that the antennas were 14-jointed. 

 Rev. T. A. Marshall described Aphid ins brassicce from the 

 same host in 1891. Rev. Marshall had seen, in addition to 

 Curtis's figure, a single specimen purporting to represent 

 Curtis's species, and which he stated was a female, in which 

 the antennas were 16 jointed, and he was therefore doubtful 

 of the identity of that species. He stated that the specimens 

 of A. rupee Curt, with 14-joiuted antennas were probably the 

 same as his own .4. brassiap, but would venture no opinion 

 regarding the specimen he had with 16-jointed antennae. In 

 the mean time, Mr. E. T. Cresson had described an American 

 parasite of Aphis hra^sicce, calling it Trioxvs piceus. Dr. 

 Ashmead received several specimens named J^rioxvs rapce 

 Curt, from Mr. E. A. Fitch, of England, and determined them 

 as identical with Cresson's species, but as he was in some 

 doubt as to the true generic position of Curtis's species he was 

 doubtful whether these specimens were correctly named. 



The writer recently sent specimens of the American para- 

 site to M^ Claude C. Morley, of the British National Museum, 

 for comparison with Marshall's types. Mr. Morley writes 

 that they are "without doubt" the same as the types of A. 

 brassiccp. Unfortunately the types of .-1. rapcr are in Aus- 

 tralia and therefore not available for comparison. However, 

 it is established that Trioxvs piceits Cresson and Aphid/i/s 

 brassicce Marshall are synonymous. Curtis's description of 

 A. rapce agrees with both these species, and Marshall believed 

 his species and the individuals of A. rapce with 14-jointed 



