224 Annals of the Carnegie Museum. 



Abdomen dark brown with the following pale brown or yellow mark- 

 ings : a spot on each side near the hind end of 2 ; a narrow transverse 

 stripe on the median suture of 3-6, between which and the anterior 

 end of each of these segments the mid-dorsal surface is indefinitely 

 paler ; a triangular mid-dorsal spot on 7-9, reaching from the anterior 

 end to more than half of the length of each segment ; a spot on each 

 side of 10. 



Abdomen somewhat compressed in 1-2, narrower and more slender 

 in 3-6, widened from the anterior end of 7 to 'the hind end of 8, 

 thence narrowing. Ventral surface of 8 just anterior to mid-length 

 with a stout process, not half as long as 8, which is bifid at tip ; apices 

 acute. 



Superior appendages twice as long as 10, a little longer than 9, yel- 

 lowish at base, brown at apex, in dorsal view almost straight, their 

 inner margins diverging, their outer margins almost parallel or diverg- 

 ing moderately, inner-upper surface of each at two-fifths' length with 

 a moderate and rather obtuse tooth, outer surface at three- fourths' 

 length with a smaller tubercle, inferior surface at one-fifth length with 

 a still smaller but acute tooth, apex of the appendage blunt, distal half 

 with many long hairs, chiefly on the inner side. 



Inferior appendage yellowish, reaching to the level of three-fourths 

 of the length of the superiors ; in ventral view with a truncated apex, 

 half as wide as the base, and terminating in two upturned denticles. 



Genital hamule yellow, almost as prominent as the genital lobe, bifid 

 at apex, branches transverse, outer branch longer, strongly hooked, di- 

 rected mesad. Genital lobe yellow, rather densely covered, chiefly 

 on its mesial side, with dark hairs. 



Wings slightly smoky or dirty yellowish. 



Abdomen 38-40, hind wing 35 ; costal edge of stigma of front wing 

 2.5 mm. 



These males much resemble those of N. androgynis Selys, but differ 

 therefrom in the appendages, the differences from de Selys' description 

 and M. Martin's figure 69 (of the appendages of androgynis) being in- 

 dicated in the above description by italics. 



The female of N. volxemi appears to differ from that of JV. andro- 

 gynis chiefly by its larger size (abdomen 38-39 vs. 37, hind wing 38 

 vs. 34 mm.) 



