3878 JOURNAL, BOMBAY NATURAL HIST, SOCIETY, Vol. XXVIII. 
animal matter, but others do so whilst living in or on live animals 
some as parasites, others as commensals. A study of the habits of 
allied species as they advance along the road to parasitism ought to 
throw light on the gradual stages by which the strictest parasitic 
habits have been evolved, The Phorid larvae are cylindrical and 
tapering towards the front. All that had then been observed as to 
life habits and metamorphoses was collected in 1883 by Brauer. * 
From this it appears that the larvae, as a rule, live in other insects 
(both living and dead) as well as in almost any sort of decaying or- 
ganic matter. Certain species show a predeliction for human. corpses. 
It seems established that each individual species of larva is not inse- 
parably bound to any definite host or even to any special sort of 
nourishment. The most varied habits have been observed in one 
and the same species. From this it may be inferred that parasitism, 
where it occurs, is a newly acquired habit. A number of Phorid 
larvae live in ants nests. Apocephalus is a parasite and Metopina 
is commensal. The parasitic larva lives in the head of the adult 
ant which finally drops off. The commensal larva lives curled about 
the neck of the larval ant and partakes of the food given by the 
attendant worker ants. Other Phorids have attached themselves 
to termites, while others are found in the nests of fossorial bees and 
wasps. It would be instructive to know what they do and what 
they feed on in the nests. 
Pipunculide. This is a small family of rather obscure and minute 
flies; but they are found in most portions of the globe and there 
are a number of Indian species which have been very little studied. 
So far as their habits are known the larvae are always parasitic in 
the bodies of Rhynchota. The Homopterous leaf-hoppers belonging 
to the families Jasside@ and Fulgoride are much attacked and also 
the spittle-insects or Cercopide. The important genus is Pipunculus 
Latr. with about 80 described species represented in every continent. 
Verrall considers the family the most exquisite fliers in the order 
Diptera. They can remain poised, without ever touching the sides 
in a glass tube not more than half-an-inch across. This power is 
made use of by the female when laying her eggs on the Homopterous 
host. She has been observed beating to and fro over the herbage 
and then, on perceiving the species of insect for which she was search- 
ing, hovering motionless like a kestrel and finally pouncing when 
the position of the victim was favourable. 
To assist in this parasitic business the flies have developed at least 
three sets of interesting features. First come the enormous eyes. 
The head is nearly spherical, actually broader than the thorax, and 
composed chiefly of the large eyes. The front facets, which in both 
* Dr. F. Brauer ‘Die Zweifliigler des Kais. Museums zu Wien’. Denks. Kais. 
Ak. Wiss. Wien. (1883) Vol. 47, at p. 66. 
