68 BULLETIN 38, UNITED STATES NATIONAL MUSEUM. 



Peridronia occulta Liuu. 



1767. Linu., Syst. Nat., iv, 514, Noctita. 

 1816. Hiibu., Verzeicliniss, 218, Eiirou. 

 185Ji. Gueu., Noct., ii, 76, A])lecta. 



1874. Grt., CaE. Ent., vi, 13, 70, Ettrois. 



1876. Speyer, Stett Ent. Zeit., xxxvi, 204, Jjj?tc<a. 



Ground color rather dark asb gray; irrorate witli smoky brown ;iiiac- 

 ulation smoky to black. Transverse lines moderately distinct, faintly 

 gemiuate, basal line scarcely evident, a slightly darker indehnite basal 

 shade. T. a. line luniilate, moderately even, outer line most distinct. 

 T. p. Hue outwardly bent over cell, theuce obliquely inward to hind 

 margin. Inner line lunulate, almost creuulate, outer line even absorbed 

 by a dusky shade reaching half way to the s. t. line. S. t. line slightly 

 sinuate, well-defined by a series of rather large, black sagittate spots. 

 A row of black terminal dots. Through the median space is an indefi- 

 nite dark shade, most evident between the ordinary spots on claviform. 

 (Jlaviform outlined ; moderate iu size; ordinary spots large, concolor- 

 ous or paler ; orbicular rounded, incompletely closed above ; reniform 

 kidney shaped. Secondaries blackish, fringes clear white. Beneath, 

 uniform smoky gray. Head and thorax like primaries; abdomen 

 darker, smoky. 



Expands 50-53""" ; 2-2.12 inches. 



Habitat. — Northern and Eastern States, Canada. 



Easily distinguished by its large size and pale color. It seems not 

 uncommon, though never taken in large numbers. ImpUcata Lef. (Ann. 

 Soc, Ent. Fr. v, 394 i)l. 10 f. 4, Iladena) cited as synonymous or va- 

 rietal to this species I consider distinct, though nearly allied. As I can 

 not find authentic record of the species as American, it is here omitted. 



Peiidioma praefixa Morr, 



1875. Morr., Proo. Bost. Soc. N. IL, xviii, 117, Agroiis. 



Ash gray, macnlation smoky or black, somewhat sparsely irrorate 

 with blackish. Basal line distinct, geminate; a small, dark, basal 

 patch. T. a. line sinuate; evenly oblique outwardly. T. p. line dis- 

 tinctly geminate only at inception, creuulate, nearly parallel in course 

 with outer margin. S. t. line pale, relieved by the distinct smoky s. t. 

 shade and by a more indefinite outer shade uot reaching either margin. 

 A lunate dark terminal line. A faint, rather narrow, median shade; 

 space between ordinary spots, dusky. Claviform very distinctly and 

 broadly outlined ; ordinary spots, large, concolorous, or paler. Orbic- 

 ular, rather oblique, oblong, open above; reniform upright, kidney 

 shaped but rather narrow, and with an unusually straight inner line. 

 Secondaries rather pale, fuscous, darker outwardly. Beneath gray, 

 irrorate, with-fuscous brown ; primaries, with somewhat paler terminal 

 shade; secondaries, with darker extra discal shade and discal lunule. 



