ORTALIDiE . 
635 
Ortalim. 
Rather small hut not minute flies, the body generally smooth and shiny, the 
wings nearly always marked with dark hands or spots, the sub-costa 
distinct and meeting the costa at an acute angle, not as in Trypetidce. 
Anal cell indistinct. The front broad, not bristly all the way down 
the sides. Female ovipositor prominent and horny. Tibiae without 
preapical bristles, only the middle pair with spurs. 
This family contains a number of species of diverse form, and some 
of them much resemble Trypetidce in appearance. Little is known of 
their life-histories, but it seems probable that these are of the same type 
as those of Trypetidce and Chloropidce, that is to say, most of the larvae 
are likely to inhabit the leaves and stems of plants, though some may 
breed in decaying matter : they are not yet known to be of economic 
importance in India. One of the commonest species in this country 
is that figured on PL LXVII, fig. 5. Ulidia oenea, F., a beautiful little 
fly of shining blue-green and copper colour which may often be seen 
sitting basking on leaves and slowly raising and lowering its forelegs 
one after another, as though it were delivering a weighty discourse 
on some serious subject. The reason for this curious habit is unknown, 
but it suggests that the fore leg might have some sensory function 
and serve as a kind of auxiliary antenna. This particular species is 
unlike most Ortalids in having unmarked wings, the banding and spot¬ 
ting of the wings being very characteristic of the family as a whole. 
Indian Ortalidce still require to be worked out from the systematic 
point of view. The more important genera are Rivellia, Ortalis, Ulidia, 
and Loxoneura. For details Van der Wulp’s catalogue may be referred 
to, and for further descriptions the writings of Coquillett (Proc. Ent. 
Soc., Washington, VI) and Kertesz (Tijdsch. V. Entom. XXIII, and 
Termes. Fuzetek., 1897). 
