962 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXVIII. 
legs in fact have become modified so as to form organs for clinging 
rather than for locomotion. 
The wings, on the other hand, are less strong than the normal 
Dipterous type. The costal vein extends about three quarters of 
the length of the wing and the sub-costal only half the length. Along 
the anterior margin of the wing there are a number of veins in close 
proximity, but the posterior part of the wing is weak and reduced. 
There are no veins to support and strengthen the membrane. AVhen 
the wings are closed they are crossed like a pair of scissors and cover 
or conceal the abdomen of the fly.* The wings in fact are becoming 
atrophied as organs of locomotion. 
The general colouring of the^e flies is brown, mottled, with yeUow 
on the thorax and legs. They are found cm horses, occasionally, 
as well as on cattle ; but they can be distinguished from H. equina 
L. which is essentially a parasite of horses. H. maculata is an Indian 
or South Asiatic species. It was introduced into Madagascar with 
Indian cattle. During the Boer War it was introduced into South 
Africa in the same way and is apparently established there. 
The travels of these parasitic flies in company with their hosts are 
illustrated in the case of H. capetisis well-known in India and Ceylon 
as a pest of dogs. It is a fly of hot countries with habits somewhat 
similar to the last mentioned species. It is now found on the shores 
of the Mediterranean and down the East African coast as far as the 
Cape. There it has long extended its range into the interior. From 
Africa it also ranges eastward across Southern Asia as far as Korea 
and Japan. Such a geographical distribution can only be explained 
by man’s action. We do not know the original habitat of this dog 
parasite, but it has evidently accompanied the friend of man in its 
travels with its master. 
The Indian Hippoboscids which are found on birds are very imper- 
fectly known but there must certainly be numerous species belonging 
to the two sub-families OrnithoniyiinrB and Olfersiince. All forms 
of birds appear to be victimised and the parasites of the birds seem 
to be less particular as to their host than those which attach themselves 
to mammals. The same fly has been collected from widely different 
birds. The parasites migrate naturally with their hosts and certain 
species of these flies such as OniitJiomyia avicularia L. are found almost 
all over the globe on all sorts of birds. On the other hand one genus 
of fly (Stenopteryx) is associated with the swallow-family and another 
(Oxypterum) vfith the swift-family. Why this should be we do not 
know at present, but may some day discover. 
Streblidcc. The flies of this small and little known family are for 
the most part ecto-parasites of bats. One Central American species 
* The reader will find a good coloured figure of U. inaculata in “ Indian Insect 
Life ” by H. Maxwell-Lefroy, Calcutta, 1909 (Plate LXIX. fig. 7.) which will enable 
the above description to be followed. 
