204 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



siders any difference between the sexes outside of the primary 

 sexual characters to be such. Mr. Barber then asked what 

 one was to do in such groups as the Strepsiptera and the 

 coleopterous group Phengodini, in which there is not a single 

 structure common to the opposite sexes. 



Dr. Hopkins interpreted secondary sexual characters as 

 those external characters which are peculiar to either sex and 

 finds that the combination of these characters on both sexes 

 of the same species serve as good generic characters. 



Mr. Knab said that in the Diptera he considered the em- 

 ployment of secondary sexual characters objectionable. These 

 are often misleading; as similar modifications may rise in- 

 dependently at different points they can not be relied upon as 

 indications of relationship. 



Mr. Walton said that in the Tachinidse the late Mr. Co- 

 quillett quite successfully and wisely avoided the use of 

 secondary sexual characters in the delineation of his genera. 

 On the other hand, Mr. C. H. T. Townsend has made very 

 general use of these characters in erecting genera, even when 

 the genotype happened to be a unique. The genus Ennyomma 

 Townsend was erected on a unique male solely because of 

 the fact that this specimen possessed hairy eyes. This genus 

 was split off from Myiofihasia B. & B. In a series of 24 speci- 

 mens of Mytophasia cenea Wied. reared as parasites of Chal- 

 codermus ceneus Boh. by G. G. Ainslie, of the United States 

 Bureau of Entomology, at Clemson College, South Carolina, 

 the males have hairy eyes and the eyes of the female are bare. 

 The amount of pilosity of the male eye varies from a few 

 scattered hairs to the densely hairy form. Notwithstanding 

 this, Mr. Townsend persists in declaring that "the genus may 

 be distinguished from both Myiophasia and Phasioclista by 

 its thickly hairy eyes." From the above-mentioned facts, 

 however, it will be seen that this hairiness is extremely variable, 

 and at best is a secondary sexual character, and as such, in 

 Mr. Walton's opinion, should not be used as a primary char- 

 acter for the erection of a genus in Tachinidse. 



Dr. Gill remarked that supplementary sexual characters 

 developed independently of the real sex organs are used to a 



