C\ xi? ) 
a kilometre away from sidae’s special locality, but it is also 
common enough where szdae flies.” 
THE HABITS OF Two ALGERIAN DipTERA—AN ASILID AND 
AN Oncopip.—Prof. Poutton exhibited a female of the 
Asilid fly Heligmoneura brunnipes, F. (Asilus castanipes, 
Meigen), together with the Oncodid (Cyrtid) fly Physegaster 
maculatus, Macq., both from Batna, Algeria—the Asilid dated 
July 2, 1909. Neither of these was present in the British 
Museum collection, but Mr. EK. KE. Austen had kindly named 
them from H. Lucas’ “ Expl. Sci. de l’Alger.,” 1849. The 
Oncodid Mr. Austen considered to be the same species as that 
represented in fig. 6, plate iii of vol. 11 (p. 445), the Asilid that 
represented in fig. 8, plate 11 of the same volume (p. 440). 
The two specimens had been sent by Dr. Adalbert Seitz with 
the following interesting notes upon their habits :— 
“‘ There is to be found upon the wing from the end of May 
until August a horrible fly, a great danger to all day-flying 
insects. I found the largest butterflies killed by it, for in- 
stance: Papilio podalirius, P. machaon, Argynnis pandora, 
Colias edusa and P. daplidice. Anthocharis eupheno I found 
only once, for this species is over before the Asilid is common. 
I observed a common Noctuid moth, Thalpochares albida, 
which rests on the thistles, but never flies by day, and this is 
exceptional, for all T’halpochares are day-fliers. Once I dis- 
turbed two 7. albida on the ground, so that they had to fly, 
and immediately they were caught by the Asilids. I also 
found plenty of Anisoplia, Cicadidae, etc., etc., caught by the 
Asilid, and sometimes I found the females devouring their 
own males.* But I did not observe the capture of a single 
Zygaenid moth, although they fly in numbers amongst the 
voracious Asilids. Nor did I observe the capture of a Myla- 
brid beetle. Together with the Asilid I send another fly, an 
Oncodid, upon which it preys. This fact astonished me; 
for the Oncodid hovers like a Syrphid in the holes made in 
the ground by spiders. The short wings enable it to hover 
even in narrow holes, and it hums so loudly as to attract 
* Dr. Seitz once found a female in copula with one male and 
devouring another, all three insects being of the same species, viz. 
H. brunnipes.” A pen-and-ink sketch of the three accompanied the 
exhibit. 
PROC. ENT. SOC. LOND., 111. 1913. D 
