PIKKIXAK: IMKUI.S OLEKACEA. 



193 



more ciirveil than In the other .species. Wings rather lightly powdered at the extreme 

 base. Init especially upon tho nervuri's witli dark grlsoons ; the basal two-fifths to one- 

 half of the costal Imnler as far as the upper limits of the cell, ami somotimes the upper 

 base of the cell itself, similarly but generally more lightly llecked; the whole costal 

 edge Is blackish fuscous, besides wliicli the apex of the wing is generally marked lightly 

 with fuscous by a narrow edging at the extreme tip, or it is more extensively nuirked 

 by a broad border to the tips of the subcostal ncrvures, sometimes deepening almost 

 to blackish fuscous, but interrupted in the mlddlcof the interspaces; very rarely there 

 is a faint open cluster of dusky scales scarcely beyond the middle of the upper median 

 interspace. Fringe uniform white. Iliiid wings very slightly and roundly angnlated 

 in the middle of the upper subcostal interspace, not conspicuously prominent in the 

 upper half of the outer margin. Wings seldom so heavily begrimed with fuscous as 

 the fore wings at the extreme l>asc and sometimes wlioUy immaculate; only the outer 

 half of the costal edge is dusky and occasionally there is a faint cluster of grayish 

 scales just below the tip of the upper subcostal nervnle; tlie darker markings of the 

 under surface sometimes show through the delicate wing; fringe uniform white. 



Beneath white, the apex of the fore wings andthewholeof the hind wings delicately 

 waslicil with faint, pale yellow. Fore wings : the yellowish wash, whicli is sometimes 

 scarcely visible, affects nearly all the upper apex of the wing beyond the last divarica- 

 tion of the subcostal nervurc, generally asfar along tho outer border as the middle 

 of the upper median interspace, but sometimes nearly, though faintly, to the lower 

 outer angle; the ucrvules crossing tlie yellowish Hold are generally narrowly bordered 

 with fuscous, more l)roadly in the middle than at either end, tlieir tips l)cing but 

 slightly fuscous. Fringe uniform white. Hind irinr/s rarely wholly imm.acnl.ate and 

 uniform ; generally the yellow is slightly deeper along the costal border than elsewhere 

 an(V deepens to a faint orange over the precostal nervnle, the Inner border is a little 

 paler tlian tlic rest of the wing, and in addition all the nervnres, excepting sometimes 

 the nervule closing the cell, are edged rather narrowly with grayish scales, while often 

 an additional line of grayish scales crosses the celllongitudin.ally — the exact continua- 

 tion of the lowest subcostal nervule, merging in the subcostal nervure a little before 

 it reaches the base. Fringe uniform white. 



Upper half of abdomen black, covered rather profusely al)ove with white scales and 

 hairs, mostly with hairs toward the l)ase, on the sides witli dull white scales; beneath 

 white, covered profusely with white scales and hairs, sometimes tinged witli yellowish. 

 Upper organ of male abdominarappeudages (35 : 15, Ifi) reaching fully to the tip of 

 the clasps ; hook, as seen from above, tapering equally throughout in continuation with 

 the centrum to a fine, slightly dovn-curved point. Clasps with the lower border entire. 



Described from fifty spceinicns, of which Z'l are ,5 , 12? . 



Dimorphic forms. PiKitis oleuacea rmtiiDA. This spring type dill'ers from the 

 autumn type in that the extreme base of both wings and the apex of the fore wings 

 are more heavily marked inclining to blackish. But the greatest distinctions are to be 

 found upon the under surface, ■which is almost invariably quite heavily washed with 

 lemon yellow on the hind wings and the apex of the fore wings: it has also all the 

 nervnres of the hind wings heavily and broadly bordered with blackish fuscous ; also the 

 nervnres of the apical half of the fore wings above the middle median nervule pretty 

 heavily, and most of the others narrowly edged in a similar manner ; it is a little smaller 

 than the summer broods. 



In the southern limits of the distribution of this butterfly the spring brood appears 

 with no tinge of yellow upon the under surface excepting faintly along the costal mar- 



150 



