INDIAN BLOOD-SUCKING INSECTS. 
663 
being carried on in this country with a view to deciding their relative 
importance in this connexion. (Leese). 
While the Indian Hippoboscidce , Muscidce, and Tabanidce are primarily 
pests of horses, dogs, and cattle, the remaining families of Diptera 
attack man freely, though they none of them confine their attentions 
entirely to human beings ; the bull-flies or 4 ‘ buffalo-gnats 5 ’ (Simu- 
liidce) are said to bite so fiercely and impartially as to render certain hill 
districts practically uninhabitable during part of the year, either for 
man or beast, and the ferocious little sand-flies of the plains are well- 
known as disturbers of our slumbers. No very serious study of the 
Simuliidce, or of Chironomidce or Psychodidoe seems to have been made 
from the medical or veterinary point of view, attention having been 
mainly directed to following up and extending the original researches of 
Ross and others on Mosquitos, but the possibility of sand-flies trans¬ 
mitting disease would seem at least worth investigation in this country. 
As far as the Indian species of Culicidce are concerned, reference to 
the list will show that we have about a hundred species at 
present known, though it is certain that a considerable number still 
await discovery. Of these only a part act as disease-carriers ; and, of 
those species known to be capable of- so acting, not all have been found 
actually carrying disease-parasites in nature, but have been proved by 
experiment to be able to carry them. It is not improbable that all 
species of the genus Anopheles will be found capable of carrying the 
malaria-parasite. The commonest Myzomyia (M. rossi) is not a natural 
malaria-carrier, but M. culicifacies, christophersi (= listoni) and Tur- 
khudi are. Of the genus Nyssorhynchus, N. stephensi, fuliginosus, 
Indiensis , and Theobaldi are carriers ; perhaps also Cellia albimana. All 
these species are Anophelince. Among the Toxorhynchince and JEdince 
none are known to convey disease, but the Culicidce include several 
dangerous species. Of these by far the commonest is Culex fatigans, the 
common brown household mosquito of Northern India. This insect 
carries the worm-like parasite (Filaria) which is the cause of various 
painful and unsightly conditions grouped together as “ Filariasis ” 
and including elephantiasis, lymphangitis, and divers varicose affec¬ 
tions particularly common in South India. Culex fatiganS has been sus¬ 
pected of complicity in the spread of some other diseases, but hitherto 
without definite proof. Another Culicine genus, Steyomyia, is abundant 
in India, the commonest species being S. scutellaris , which seems to be 
widely spread. A closely related species, S. fasciata , occurs, in Bengal, 
in the neighbourhood of Calcutta, and this particular species is well 
known to be the carrier of yellow fever in the West Indies ; whether S. 
scutellaris can also convey this most deadly disease is unknown. 
The question of the chances that yellow fever may be introduced 
into India in the near future is one which merits perhaps more than a 
passing glance, and we venture to borrow a passage on this subject 
from Manson’s “ Tropical Diseases.” “ The probable reason of the 
non-introduction (of yellow fever) into Asia is that the trade route from 
