ISOCHAETES. By H. G. Dyar f. 
1131 
E. aquapennis Dyar (166 g) resembles cypris, but it is somewhat larger, with more oblong wings. The aquapennis. 
median area is broadly lighter behind the cell, the discal dot extinct. Expanse of wings: <$ 26 mm; $ unknown. 
British Guiana. 
E. hydropteris sp. n. (166 g) resembles aquapennis , but it is much larger. Expanse of wings: <£ 33 to hydro pterin. 
35 mm; $ unknown. From Costa Rica (Sixola River, in March; Tuis, in May), Schaus & Barnes. Types in 
the U. S. National Museum. 
E. cypris Grt. (166 g). Forewing tinged with lilac at the base, a large spot from the centre of the cell cypris. 
almost the margin is lighter, shaded brown in its inner-marginal half, bordered by an undulating white line; 
a brown band in the distal third of the costal-marginal part is as broad as the narrow marginal area, which 
is dark brown dusted with red; discal dot rather distinct. Hindwing scarlet; Expanse of wings: 25, $ 33 to 
37 mm. The larva was bred by Jorgensen, but not described. Paraguay. 
E. albiplaga Her. <f- Hopp differs from the following natadoides in a purely white spot on the hindwing albiplaga. 
covering the exterior half of the cell and the basal halves of the veins 1—4; the red area above the middle of 
the inner margin is srftall and narrow. The light dentate subterminal line shows a dent before the apex. 
Expanse of wings: $ 30 mm; $ unknown. Brazil (Tonantins, Amazons). 
E. natadoides Dyar (166 h) is dark rusty brown with two dark purple grey spots, one at the base, cut natadoides. 
by an oblique lighter line, and a subapical one traversed by a line in the reverse direction, so that both terminate 
near together at the costal margin. Hindwing bronze black, fringe light. Expanse of wings: <$ 24 mm; $ un¬ 
known. Brazil (Paranapanema, Sao Paulo). 
E. pullum Her. <b Hopp. Forewing almost monotonously blackish brown, finely strewn with bluish pullum. 
white, and with a small round dark discal spot; a distinctly defined area in the distal half of the inner margin 
and at the anal angle is of a brighter brown; a small white blotch behind the lower cell-angle. Hindwing dark 
brown, fringe light. Expanse of wings: $ 27, $ 32 mm. Peru, Ecuador. The $ type may belong to the genus 
Isochaetes ; the $$ may be wrongly ranged here, I did not examine any good specimens. 
E. cupreitincta Dyar (166 h) is blackish brown, with a slight bronze reflection, the forewing with in- cupreitinda. 
distinct black undulating lines; subterminal line uniformly dentate, parallel to the margin; a large light yel¬ 
lowish spot behind the cell down to vein 2, an extensive copper-red area, rarely blackish, is in the middle of 
the inner margin. Hindwing rather dark, dusty blackish. Expanse of wings: $ 18—22, £ 25—30 mm. Guate¬ 
mala, Costa Rica, Colombia, Venezuela, Guiana, Brazil (Amazons). 
31. Genus: Isochaetes Dyar. 
Palpi projecting beyond the vertex, the last joint half the length of the long 2nd joint. Fore wing with 
separately arising veins 2 and 3. Hind tibiae wit h both the pairs of spurs. 
Type: I. beu.tenmuelleri H. Ediv. 
1. beutenmuelleri H. Edw. (166 h). light tan-coloured, marbled with brown, with a round postcellular beutenmuel- 
spot, very conspicuously bored with violettish grey. Hindwing shaded brown, fringe light. $ intensely dusted 
with violettish grey, similarly marked, with a light spot at the costal margin. Hindwing blackish, fringe light. 
Expanse of wings: 12 —16, $ 17—19 mm. Larva purely grass green, with a series of long, feather-like, glassy 
horns on each side; it lives on the higher branches of oaks. New York, Maryland, North Carolina, Florida. 
I. rufescens Sells. (= mexicanum Her. & Hopp ) (166 h). light tan-coloured as in beutenmuelleri, the rufescens. 
wings more pointed, more irrorated with brown, the bent light area at the cell-end with an interior dark line, 
but not a round spot. Expanse of wings: ^ 17 mm; $ unknown. Mexico, Guatemala. 
I. marina Dyar (= cupreitincta Her. & Hopp nec Dyar) (166 h). Forewing of <$ dark reddish brown marina. 
strewn with bluish scales, the marking more dinstinct than in the §; the centre of the wing is traversed by 
an indistinctly defined yellowish band, a dentate dark shadow before it and a dentate dark line behind it; a 
light elliptical postcellular area is filled with brown, a double light spot is between veins 3, 4 and 4, 5, the same 
in the §; irregular light spots at the margin. Hindwing blackish brown. The $ is intensely dusted with dark 
violettish grey and strewn with blue scales, a dark streak at the cell-end and an exterior brown line, excurved 
around the cell-end and enclosing a light curved area behind the cell; the wing on the whole dark with ob¬ 
literated markings. Expanse of wings: 21, $ 22—24 mm. French Guiana, Brazil. 
1. ashtabel Dyar (166 h) has dark purple brown forewings, with red-brown spots in the basal area, a ashtahcl. 
black acutely angled zigzag line in the middle, bordered with red-brown outside and forming a deep inden¬ 
tation below the median vein; a dark exterior line excurved around the cell-end encloses a curved light area 
at the cell-end, oval in the upper half, darkened except two whitish spots below. Hindwing bronze black. 
Expanse of wings: 18, $ 26 mm. British Guiana. Paraguay. 
