1864.] 
437 
described from a possibly faded individual referable here. Having 
however forwarded a specimen to Mr. Walker of the British Museum, 
that distinguished Entomologist gives it as his opinion that the present 
species had not been hitherto described, in which opinion I now concur. 
Although the markings present many coincidences with M. Gruenee’s 
description, yet the peculiar greenish or olivaceous coloring of the an¬ 
terior, and darker posterior, wings, together with the absence of the 
thoracic markings of M. fragilis, form good specific distinctions which 
will not allow of the two species being confounded. 
Genus ACRONYCTA, Ochs. 
Acronycta noctivaga nov. sp. (Plate 9, fig. 3.) 
Anterior wings dark grey varied with black; ordinary lines white. 
Basal space black, greyish on the costa; basal half line white, bordered 
externally by a black line. Transverse anterior line white, widely lunu- 
lated, distinct, bordered externally by a black line which commences 
from a broader black costal mark. Median space large, dark grey; 
median shade band blackish, traversing the reniform spot. Ordinary 
spots of the normal shape, distinct; reniform attenuated, black, with a 
hardly perceptibly lighter center; orbicular round, black, with an ill- 
defined greyish inner ring. Between the ordinary spots in the lower 
middle of the wing is a squarish black spot bordered externally by the 
median shade. Transverse posterior line white, acutely dentated, arcu¬ 
ated superiorily, preceded near the costa by a whitish mark and bor¬ 
dered on either side by a black line. Sub terminal line broad, white, 
irregular, interrupted just before the internal angle. Terminal space 
black, narrow, reduced by the subterminal line which, at about the 
middle, nearly attains the external margin. Fringes white interrupted 
with black between the veins; costa with some black and white marks. 
Posterior wings uniformly dark brownish, immaculate; fringes lighter. 
Under surface of both pair light brownish, with faint discal dots and 
bands. Thorax grey, varied with blackish on each tegula and collar. 
Head whitish grey, with two longitudinal parallel black marks between 
the antennae, latter blackish, powdered with whitish at base. Palpi 
with the second joint black tipped with whitish, legs greyish; tarsi 
black, white at extremities; abdomen blackish grey, crested on first 
segment. % Exp. inches. 
Tlah. Penn., New York. Bare. Coll, Ent. Soc. Philadelphia. 
