June, I9II.] PeARSALL: ANOTHER SpECIES OF PeRO. 91 



forms of the same species, because no early records of niodestus, as 

 I have limited it, are obtainable. I have given, in describing it here- 

 with and with great satisfaction, the name of 



Fig. I. Male genitalia of Pero grossbecki sp. nov. 



Pero grossbecki, new species. 



Expanse 30-32 mm. Palpi and front dark gray, the former tipped with 

 white. Vertex paler or whitish in some cases. In all my examples a white 

 line crosses front below antennae, which are yellowish white barred with dark 

 gray basally. Thorax an even dark gray. Abdomen paler, finely flecked with 

 black. The front and thorax are often washed with purplish. Ground color 

 of wings above, ashen darkened by a sprinkling of black atoms, heaviest over 

 median area of primaries, and gathered into short strigations over basal area. 

 Inner line of primaries black, clearly defined, strongly scalloped, that beneath 

 costa larger and longer. Median area heavily sprinkled with black and hav- 

 ing an irregular heavy black shading across wing, within outer line, paling 

 out centrally. This area is sometimes tinged with pale chocolate, but never 

 exhibits the ruddy brown of modestns, nor the patch of rusty scales, near to 

 or surrounding the discal dot, as in that species. Outer transverse black line 

 clearly defined, strongly sinuate. Outer space paler and smoother ; a broad 

 pale, purplish ashen band, becoming a whitish irregular line at center, suc- 

 ceeds the outer line — beyond that to margin a little darkened. Marginal black 

 line not present in its entirety in even the best examples, but often running 

 only from angle at vein 4 around anal angle to median area, heavier and 

 darkened at the latter portion. Intervenular white dots varyingly present, 

 that between veins 3 and 4 ringed with black, or entirely black. Fringe like 

 ground color. Discal dots small linear or angulate, white. Transverse line on 

 secondaries black, bordered externally with white and much waved, the convo- 

 lutions smaller toward costal region. Outside this line to margin the wing 

 is paler, except at anal angle where black scales are clustered, and the marginal 

 line becomes broadly black, sending inward between veins, two or three black 

 triangles. A white dot circled with black between veins 6 and 7 at margin 



