166 
Psyche 
[ December 
ously distributed species in the New World, namely V. com- 
stocki Wheeler of California, opacus Coquillet (possibly 
only a variety of comstocki) of California and New Mexico, 
tibialis Walker of Jamaica and Cuba, and fascipennis Wil- 
liston of Mexico. The only other species, the genotype 
V. vermileo Linn., is confined to the Mediterranean region. 5 
On the approach of winter the larvae collected by Mr. 
Dow were placed in a cold room and not brought into the 
heated laboratory till April 1, 1931. They at once became 
active, excavated fresh pitfalls and greedily seized and 
sucked the juices out of the ants, termites and meal-moth 
caterpillars with which they were provided. Some of them 
pupated in late May and several perfect flies of both sexes 
emerged during the period from June 10 to July 5. A 
day or two before emergence the brown, sand-incrusted 
pupa wriggled up through the sand till one or two milli- 
meters of its anterior end projected into the air, and a few 
hours before emergence vigorously thrust its entire body 
out till it lay freely exposed on the surface. Then, usually 
in the early morning, the exquisite imago escaped from 
the pupa-case and was able to fly within two or three hours. 
It is a very delicate, short-lived, positively heliotactic insect 
which, unless very carefully handled, loses its legs quite 
as readily as many crane-flies (Tipulidse). 
Comparison of my Cuban specimens with Walker’s brief 
description of the Jamaican V. tibialis reveals certain slight 
differences which are scarcely more than varietal or sub- 
specific. Walker, however, was not noted for the adequacy 
of his dipterological descriptions, so that the recovery of 
the true Jamaican tibialis must be awaited before the pre- 
cise status of the form discovered by Mr. Dow can be deter- 
mined. 
5 The South European, Balearic and Egyptian localities in which 
this species is known to occur are listed in the “Demons of the 
Dust” (pp. 147-150). I there predicted its occurrence in Sicily, 
unfortunately overlooking the fact that it had already been taken at 
Taormina on that island by my friend Horace Donisthorpe (The Ants 
[Formicidse] and some Myrmecophiles of Sicily. Ent. Rec. 38, 1926, 
pp. 161-165, 39, 1927, pp. 6-9; and the Guests of British Ants, London, 
1927, p. 120, fig. 21.) 
