80 BULLETIN 38, UNITED STATES NATIONAL MUSEUM. 



Expands 35-39'""' ; 1.40-1.56 inches. 



Habitat. — ISToitliern and eastern United States, Canada. 



This species has been very generally confounded M'ith the European 

 triangulum, from ^vhich it is nevertheless perfectly distinct. Mr. Grote 

 in describing the species, Dr. Speyer in describing ohtum. and after- 

 ward Dr. Zeller pointed out the differences in ornamentation, which, 

 however, are not greater than the variation observed in allied species. 

 Mr. Grote found a structural character in the antenna} which have a 

 stout bristle on each side of each joint, beside the usual cili;B. In addi- 

 tion the genitalia of the $ show evident differences; they are so nearly 

 of the same type that comniunity of descent is demonstrated, but the 

 inferior finger on the harpes is in triangulum reduced to a mere acute 

 spur, and there is no accessory piece furnishing the base of clasper and 

 exceeding the harpe. On the contrary, the clasper arises from the 

 thickened, corneous margin of the harpe and is of almost identically tlie 

 same shape as nonnaniana. 



The peculiar yellow gray color, and the contrasting black cell furnish 

 well-marked characters to separate the species. 



Lederer says of triangulum '' shienen unbedornt." Speyer says this is 

 error, but the spines are very short and indistinct. In our species they 

 are very evident. 



Noctua esurialis Git. 



188L GrL.Can.Eut. XIII, 131, Agrotis. 



"This species has all the tibiie spinose. In color it is like perconjlua, 

 being of a pale ruddy brown over ochery. The stigmata are concolor- 

 ous, and, as in Normaniana, set in a black spot. The orbicular nearly 

 touches the reniforni inferiorly, leaving a blackish brown V-shaped 

 space between the stigmata. The orbicular is open to costa, oblique, 

 widening above, preceded by a narrow black shade on the cell, lieni- 

 form widening inferiorly, constricted, upright. Lines dark ; t. a. line 

 single, marked on costa above the orbicular, sinuate, incomplete. T. 

 p. line indicated by venular dots, as also the s. t. line, which is followed 

 by a faint narrow pale shade and is inaugurated on costa by a curved 

 mark. The species seems to belong to the series of rubifera.perconjlua, 

 Hilliana, conchis, Normaniana. Hind wings pale fuscous, with the 

 fringes and outer edge colored like primaries. Head a little paler than 

 thorax, with the palpi darker at the sides. Abdomen, at the sides and 

 beneath, tinged with rosy brown. Wings beneath tinged with ruddy, 

 especially on the margins and outside of the extra mesial fuscous line. 

 Discal marks indicated." 



Expanse 31'""^. 



Habitat — Washington. Collected by H. K. Morrison. 



Evidently allied to Normaniana, but smaller and of a somewhat 

 different color. I have nothing that I could refer to this species in any 

 of the collections studied by me. 



