196 
Psyche 
[December 
specimen. One wing was also so glued, but has been mounted in 
Euparal on a microscope slide. The generic name is an anagram of 
that of Dr. Joseph Bequaert, to whom this remarkable genus and 
its included species are respectfully dedicated. 
The relationships of this genus appear to be closest to Acanthocera, 
with which it agrees in general facies, wing pattern, shape of frons, 
etc., but from which it differs most markedly in the inflated sub- 
callus and first antennal segments. The lack of terminal antennal 
segments in the only known specimen makes detailed comparison 
unprofitable. The only other genera of Neotropical Tabaninae with 
such inflated first antennal segments are Bolbodimyia Big. and 
Oopelma End. From Bolbodimyia the present genus differs in wasp- 
like fascies, different wing pattern, shiny areas on frontoclypeus and 
genae, lack of inflated tibiae or hind tibial fringe, normal venation 
(R 2 + 3 not bent abruptly forward), and presence of marked 
vestiges of ocelli. From Oopelma it differs in much greater size, 
Oopelma being a tiny Tabanid less than 7 mm. long, in not having 
the cross-veins prominently clouded, and in having shiny inflated 
palps and sclerotized theca and labella of the proboscis. 
Oopelma appears to be an extreme development of tendencies fore- 
shadowed in certain species of Stenotabanus , e.g. St. liokylon Fchld., 
which have the first antennal segments bare and shiny, though very 
little inflated. It would appear that development of the greatly in- 
flated basal antennal segments has taken place independently in these 
three genera of Diachlorini, and is unlikely to be of phylogenetic 
significance. 
