26 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



and the eyes of the females are bare. The amount of pilosity 

 of the male eye varies. 



Mr. C. H. T. Townsend 1 has erected the genus Ennyomma on 

 a single male of this species because of the hairy eyes and has 

 since declared 2 "The genus may be distinguished from both Myio- 

 phasia and Phasioclista by its thickly hairy eyes." The hairiness 

 is variable and is a secondary sexual character at best; further 

 comment is unnecessary. Few of us will be willing to assent with 

 Mr. C. H. T. Townsend 3 that "these forms cannot be classified 

 in the ordinary way .... there is no such thing as a 

 species in the generally accepted sense," and further "the only 

 safe course to pursue is to give a name to every assemblage that 

 can be distinguished from other assemblages." etc. 



This sounds suspiciously like an acknowledgment of defeat. 

 The Muscoidean flies are subject to the same general laws of 

 development as all other insects and can probably be classified 

 without erecting a new system of nomenclature. 



Dr. S. W. Williston 4 has said "We yet know very little about 

 individual variation in this family (Tachinida?), or the real value 

 of many characters now used. The absence or presence of a 

 bristle may be found to represent a group or species, but we 

 should first learn how constant the character is in species." 



Nineteen years have since elapsed and his statement still applies 

 to the situation. The required knowledge cannot be obtained 

 with a pen and a few dried specimens, though rivers of ink flow. 

 Nor can the problem be solved by the use of the dissecting needle 

 and a vivid imagination. 



The patient study of specific variation in even a few of the 

 most homogeneous groups will certainly throw considerable light 

 on the subject and this method is perfectly practicable for any 

 worker who has the opportunity of rearing tachinids in numbers. 



As was acknowledged at the beginning of these remarks, the 

 studies herewith included are but fragmentary in character, never- 

 theless, the evidence drawn from them points quite strongly 

 toward several definite conclusions. 



1. The chsetotactic characters as at present used in the classifi- 

 cation of Muscoids are variable to a considerable degree and 

 should be tested whenever opportunity permits. 



2. These characters are in some species subject to variation 

 with the fluctuation of food supply of the larva. This phase of the 

 question must be investigated in connection with any studies of 

 specific variation. 



1 Trans. Amer. Ent. Soc., vol. xvm, p. 370. 



2 Taxonomy of Muscoidaen Flies, p. 58. 



3 Taxonomy of the Muscoidean Flies, p. 13. 



4 Insect Life, vol. v, p. 238. 



