240 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxv. 



or less blue shaded or powdered; in the female it may be merely 

 strigillate or there may be a dusky band similar to that beyond s. t. 

 line on primaries. Beneath powdery, with linear discal spots on all 

 wings; primaries with median and an extra median transverse shade 

 lines, secondaries crossed by several undulating- lines. 



Expands, 1.60-1.88 inches = 40-47 mm. 



Habitat. — Canada to Florida along- the Atlantic coast; west to the 

 Rocky Mountains; Arizona. 



Dates in the more northern part of its range are May, June, and 

 July, the latter usually worn females; from the Southern States 

 there are specimens in August. 



A series of over one hundred examples, representing the entire 

 range of distribution, is before me and gives an excellent chance to 

 determine the extent of variation. This is aided by a series of 27 

 specimens from one locality in the Catskill Mountains, taken by Mr, 

 R. F. Pearsall, which shows that the entire geographical range may 

 be matched within the limits of a single locality. 



At first sight it seems almost hopeless to attempt to describe these 

 variations; but if we separate the sexes, we find that they group into 

 types. Taking first the males, we have those in which the terminal 

 space is divided into two lunate bluish areas, and these usually have 

 the anterior portion of the median space also blue powdered. Then 

 come the less contrasting forms in which the blue is reduced to an 

 edging, or it may be an almost continuous line, as in the example 

 that formed the type of Doctor Bethune's albofasciata. With either 

 of these forms there may occur examples that have the median space 

 much paler than the rest of the wing. In the female the range is 

 somewhat less because the blue is eliminated. We have forms that 

 are almost evenly blackish except for a light sub-apical shading, and 

 forms that have the median space contrastingly paler, and every- 

 thing in between. Throughout it all, however, the species remains 

 characteristic and specimens from New York and from Arizona are 

 placed with equal readiness. 



The spinulation of the middle tibia is distinct, though not con- 

 spicuous, and sometimes there is a spinule or two between the spurs 

 of the posterior pair. The tufting on the middle femora of the male 

 is obvious and the mass of specialized scales is Large and conspicuous. 



The genitalia of the male are moderately asymmetrical, the left 

 harpe much broader at base and narrowing abruptly into an elongate 

 flattened process; the right much more elongate, narrower through- 

 out. I have examined specimens of the most divergent appearance 

 superficially, and from the extremes in geographical range, without 

 discovering any material departure in form. 



In the female the depressions on the upper surface are usually 

 well marked and the terminal segments are usually more or less 



