214 
Psyche 
[September 
Museum d’Histoire Naturelle in Paris, and Dr. Tsacas kindly 
secured for me a photocopy of the parts dealing with Diptera. 
D’Orbigny records under number 9533-37, the number borne by the 
types, that the species lives on the banks of the Parana along its 
whole length, that its bites are very painful and that the local inhabi- 
tants, who already suffer much from the attacks of mosquitoes and 
a multitude of other insects, fear this species greatly, as it torments 
them cruelly and returns ceaselessly to the attack. These remarks 
indicate that albitarsis as well as aberrans have feeding habits similar 
to crassipes, but different from Himantostylus. 
In summary, I believe that Stigmatophthalmus and Selasoma are 
both isolated and unrelated genera best placed in the tribe Tabanini. 
They may well be relatively old elements whose connections have 
disappeared. Stigmatophthalmus altivagus is a rather rare species, 
seemingly confined to the higher altitudes of the coast range of south 
eastern Brasil. Selasoma is widespread from Mexico to Brasil, but 
apparently local in occurrence. Himantostylus I believe belongs in 
the Diachlorini, but I think its resemblances to Lepiselaga are more 
likely due to mimetic convergence rather than close relationship in a 
phylogenetic sense. To me it appears closer to Diachlorus and Steno- 
tabanus than to Lepiselaga , but it is in any event rather isolated. 
I give below a key to the genera discussed here. All the species 
are black or largely so, with basally black wings, rather stout and 
chunky build, and tibiae more or less inflated. 
Key to the genera 
1. Discal cell (ist M 2 ) of wings constricted, the vein forming its 
posterior margin strongly arched upward, the cell entirely infus- 
cated. Lepiselaga 2. 
Discal cell normal, either wholly or partly hyaline, or with a 
hyaline spot. 3* 
2. Frons about twice as high as wide, parallel sided, the vertex with- 
out bare area. Notopleural lobes not strongly protruding. Body 
when undenuded clothed with greenish irridescent scales 
(Lepiselaga) 
Frons as wide or wider than high, widened below, the vertex 
protuberant and shiny. Notopleural lobes strongly inflated and 
protuberant. Body without greenish scales (Conoposelaga) 
3. Basicosta bare. Small species less than 9 mm. long. Antennae 
slender, the basal plate of third segment subcylindrical, about 
twice length of style. Three distinct ocelli at vertex. Wing 
basally black or dusky to ends of basal cells, beyond this wing 
