E. T. CKESSON', JU. 
33 .') 
Generic l)icujnosi>i . — Similar to Athyroylossn. Occllai' hi'istlcs 
l)('liii)(l or on line with the antei'ior ocellus, separated fi-om each 
other as far as the posterior ocelli are from (aich other. Arista 
with long hairs above. Fore femore with distinct fh'xor si)in(‘s 
(exco])t in mclanderi), of which the proximal one is soiiK'thnes 
slightly removed and much stouter than the otheis. Alula of 
wings linear with thickened ciliated margin. 
Genotype. — Ochtheroidea atra Williston, (18!)()). [Mono! yi)ic.] 
The facial structure is very varial)le, from evcady aiid gcaitly 
convex to distinctly subtubei-culate. In some sj)eci(‘s the 
arrangement of the setulae,and the sculpturing of the nu'sonotum 
and scutcllum, suggests a closer athnity with Gjpnnopn than do 
the others, but the facial characters otfer no correlation. The 
development of the foi-e femoral spines is also vai'iabh', l)ut in 
the material ('xainined there is always sonu* indication of 
such s])ines. 
The sexes in imuiy sp('ci('s are difficult to sei)aral(', and 1 have 
jiot attempted to do so. Some of the shining black specii's ol 
Dii^cocerina and its allies may be mistaken for sjK'cies of this 
genus, l)ut the development of the ]iost-bnccal i'idg(‘ will at 
once distinguish those l)eIonging here. 
The genus is represented by eight sp('cies in tlu' Anua'icas, 
of which three occur north of Mexico. 
Tabic of American Si)ecie.'< 
1. 
4 . 
5 . 
.\11 til)iae l)la(‘k. 
I lalteres t)lack F'**' Athyroglossa 
Haltere.s white. (Neot roi»ieal i centralis 
( )nly the fore tibiae black 
Halteres black or dark granulosa 
I lalteres white or ycH'iw ” 
Wings yellowish, with apical infuscation; scutelluin and abilomeii (I, at; 
fore tarsi pale ba.sally. (Neotropical) »tra 
Wings with discal and apical infuscation; sculelluni and abdomen convex; 
fore tarsi black basally. (Neotropical) fascipennis 
Wings inunaculate 
Mesonotum j)olished. (Neotroi)ical) lac\is 
Mesonotum obscurely shining or granulosi' •’ 
Cheeks broad, about one-halt height of eye. 
Fore femora microscopically spinose; second costal sc( 
as long as third 
Fore femora distinctly spinose; second costal section 
third. (Neotropical) 
(dieeks narrow, scarcely one-lourlh eye height 
•t ion I liree t inir> 
melanderi 
twice as long a- 
siinilis 
glaphyropus 
TRANS. AM. KNT. SOC., XLMI. 
