558 
BIPTERA. 
of species, between fifty and a hundred being known in England. Few 
are yet recorded from India (Ind. Mus. Rec., Annandale and Brunetti), 
but an examination of the walls and windows of 
bath-rooms soon shows that the insects are abun¬ 
dant in the plains as well as the hills. Two 
species are very common at Pusa (fig. 356). the 
larvae of both being aquatic or semi-aquatic, 
living in places where water constantly drips, 
or in holes in tree-stumps and similar spots, and 
feeding on green algae and other vegetable matter. 
The two largest genera are Psychoda, in which 
the last branch of the Radius ends at or in front 
of the wing-tip, and Pericoma in which it ends pj g 
behind it. 
Dr. Annandale has made the interesting dis¬ 
covery that Biflonema , a genus hitherto known 
Larva of a 
Brazilian psycho- 
PID (AFTER MULLER), 
ENLARGED. 
only from specimens 
found in 
region. 
amber, occurs in the Himalayan 
The chief importance of the family depends 
on the fact that some few species are vigorous 
blood-suckers. Until comparatively recently 
the identity of these flies in India was appa¬ 
rently hardly recognised, though one species 
had been described from Ceylon, but in reality 
these Psychodidce, belonging to the genus Phlebo- 
tomus, form the bulk of those annoying insects 
which are known as “ Sand-flies ” and univer¬ 
sally condemned. Specimens have been taken 
Fig GR 8 ov^LARVA of F Psy- fr° m a variety of localities from Calcutta to 
Pusa DA bengalensis ’ the Punjab and Bombay, and they are also 
widely distributed through South India (N. 
Annandale). The females alone bite. Their small size gives them an 
advantage over Mosquitos, since they are able to walk through an ordi¬ 
nary mosquito-net without difficulty. The ankles are a favourite point 
of attack, and the flies will even sometimes crawl under the bed-clothes 
in their lust for blood. I find their bite peculiarly irritating, much 
more so than that of the common mosquito (Culex fatigans), and it 
