64 THE CANADIAN ENTOMOLOGIST. 



desired. My note was intended for the use of students of these insects, 

 and was given to call attention to the form of the hind spur, the impor- 

 tance of which was not indicated in the descriptions because all of these 

 had the spur of the same form. 



It is nothing new to me to hear that the males of ^. viridula and A. 



fervida have the hind spurs different from the females. Indeed, I have 



never supposed that the spurs of the males of Halidus and Augochlora 



presented any important characters, though, as a rule, I have mentioned 



the form of the hind spurs in the descriptions of the females. 



In Trans. Am. Ent. Soc, XXII,, ii8, I indicated A. lucidula, Sm., 

 as a synonym of A. viridula, Sm. I intended to confirm Patton's view 

 that the former was the female of the latter, and cited the place where he 

 had expressed it. As regards the synonymy of A. fervida, Sm., and A. 

 humeralis, Pttn., the description of the male of Patton's species is the 

 only thing which leaves any doubt in my mind. I think they are the 

 same, however. Two of my specimens have the tarsi pale testaceous, 

 while a third has all except the basal joint dark, seeming to connect the 

 typical A. fervida ^ with the male described by Patton. I have no 

 doubt at all about what I have identified as A. humeralis being the 

 female of A. fervida, and that is all I have said about it. 



The females of the first division do not have the spurs " ciliate or 

 simple," but serrate with numerous fine teeth. The spurs are to be dis- 

 tinguished mainly by the number and length of the teeth, a fact which is 

 obscured by the terms "ciliate" and "pectinate." The females of the 

 second group have the spurs with only four or five long teeth. 



It is one thing to use these characters in separating the species, and 

 quite another to found named sections upon them before it is shown that 

 they are valid indications of relationship throughout the genus. If we 

 assume that Augochlora is a genus distinct from Halictus, or even a 

 natural section of that genus, we must admit that the form of the hind 

 spur is a case of parallel modification, and no proof of affinity. Other- 

 wise, we must subdivide each genus and rearrange the species according 

 to the form of ilie spur. In Halictus, I am satisfied that some species 

 with few-toothed spurs are more closely related to species with finely 

 serrate ones than to some species whose spurs are more like their 

 own. Judging from analogy, we may expect to find the same thing in 

 Au\:;och!ora. 



