2 74 Bulletin American Museum of Natural History. [Vol. XXI, 



also resembles F. difficilis Emery and notably its var. consocians 

 Wheeler except in pilosity. 



It is probable that the female of F. impexa is peculiar either in 

 being very dimintitive, like the females of F. difficilis, microgyna, 

 nepticula, etc., or in having an vmusual color like the female of F. 

 oreas. Until this sex of impexa is discovered there may be some 

 doubt as to whether the form should be regarded as a species distinct 

 from rufa. It certainly differs very markedly in pilosity from all the 

 subspecies and varieties of rufa hitherto described. 



