Publ. 4. III. 1927. 
HOMOLAGOA; TRISTYLA. By Dr. M. Draudt. 
325 
A. spreta sp. n. (47 a) differs from the preceding species in much lighter orange-yellow forewings spreta. 
with a slight brownish tint. Hindwing loam-coloured grey, the anterior body somewhat deeper orange than 
the forewing. Mexico, numbers of them in both sexes from Zacualpan without transitions to salacon. 
A. composita Edw. (47 a) is much smaller than salacon, on the forewing very lustrous orange as well composita. 
as on the head and thorax, fringes lighter. Hindwing lighter orange-yellowish with light fringes and a brownish- 
grey hue on the disc. Arizona. 
A. dulcita Schs. (47 a). Head and thorax orange-yellow, forewing somewhat lighter yellow, the extreme dulcita. 
costal margin in the basal half greyish-brown. Hindwing whitish, feebly tinted brownish-grey, at the distal 
margin and in the $ darker. Mexico. 
A. varrara Dyar (47 a) is extraordinarily similar to dulcita, but the forewing is paler yellow with varrara. 
a decidedly greenish tint, a very faint brownish-grey reflection, thorax coloured like the forewing. Hindwing 
darker brownish-grey also in the <$. Mexico (Tehuacan). 
A. pyronaea Drc. (47 a) is above on the head, thorax, and forewing of a pure white, on the hindwing pyronaea . 
blackish-brown with white fringes, just as dark is the under surface. Mexico (Guerrero). 
A. alesaea Dyar (47 a) is the same, but also the hindwing is above dingy white, at the distal margin alesaea. 
at most with a slight greyish-brown tint. Beneath only the forewing is blackish-brown. Mexico (Guerrero). 
A. melanocrypta Dyar (46 1) is considerably larger than the two preceding species, easily discernible melano- 
from pyronaea by 3 antemedian and 2 postmedian black dots. Hindwing and abdomen purely greyish-black. crypt 
Under surface quite black. Mexico (Tehuacan). 
A. plesioglauca Dyar (= comstocki Hill.) (47 a) is on the head and wings dark bronze-coloured, in plesioglau- 
the basal three fourths with a very intense blue and violet metallic gloss with 3 broad brown stripes. Hindwing 
blackish-brown. Described from Mexico (Guerrero), recently reported from Arizona. 
A. prepontendyta Dyar (47 b) externally resembles H. arivaca by the white forewing with the narrow preponten- 
orange discal area which is edged by black transverse lines and in which the small white, black-edged maculae dyta 
are, the reniform macula with a black central streak; marginal area orange with black veins and internerval 
stripes. Hindwing brownish-grey, at the margin feebly hued with orange. The species, owing to a somewhat 
differently shaped frontal appendage, strictly speaking does not belong to this genus. Mexico (Guerrero). 
A. hilli B. & Benj. (= calliente Hill.) (47 b) neither belongs here for certain, because the frontal hilli. 
appendage is like in Stiria, the habitus similar to St. hutsoni and olivalis. Forewing light olive, strewn with 
white, with 3 extinct white transverse bands, the distal band continued in an oblique apical patch, the most 
proximal band extending almost vertically to the hind-margin, the two distal ones more oblique. Hindwing 
whitish, towards the margin powdered with olive-brownish. Expanse of wings: 26 to 28 mm. California. 
203. Genus: HomoJstgoa B. & McD. 
According to Dyar’s suggestion, we place this genus here owing to the close affinity to the last white 
species of the preceding genus, as it is better ranged here than with the Erastrianae. Proboscis developed, but 
feeble, palpi erect with a rather long terminal joint, frons with a conical projection and a horny plate below 
it. Thorax clothed with scales and hair, tuftless, tibiae unarmed. Abdomen of $ with a tuft of anal wool. On 
the hindwing the lower radial branch is a little stronger developed than usual and rises above the lower cell-angle. 
Only 2 species: 
H. grotelliformis B. & McD. (47 b) is white with black palpi, the abdomen with fine black rings, grotellifor- 
both the transverse lines marked by single black dots, the anterior line by 3, the posterior line by 5 dots; fringes 
white with small black dots. Hindwing smoky grey with white fringes. Arizona. 
H. tritogramma Dyar (47 b) is extraordinarily similar to the preceding species and presumably tritogram- 
only a local race of it. It is somewhat larger, the abdomen with somewhat broader black bands, and the 
hindwing almost purely white. Mexico (Guerrero). 
204. Genus: Tristyla Sm. 
Distinguished by an uncommonly strong development of the frontal appendage which is extended 
into a long point, laterally and below surrounded by 3 short points, beneath the whole with a horny plate. 
Palpi long, straightly porrect; thorax scaled, behind with a large loose tuft, abdomen tuftless. Only 1 species: 
VII 
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