348 
C. GORDON HEWITT. 
PAGE 
5. Ophthalmia 
6. Plague . 
7. Miscellanea 
. 399 
. 401 
. 402 
. 404 
. 405 
. 412 
Vlll. Flies and Intestinal Myiasis 
IX. Literature . 
X. Appendix on the Winter Breeding of M. domestica 
I. Introduction. 
The present paper concludes this study of the structure, 
development, and bionomics of Musca domestica (the 
previous parts were published in 1907 and 1908). In it I 
have described the bionomics, certain of its allies which may 
occur in houses, its parasites, and its relation to man, especially 
as the cari’ier of the bacilli of certain infectious diseases. 
The last portion of the present paper, in which is described 
what is known concerniug the ability of M. domestica and 
its allies to carry and disseminate the bacteria of many impor- 
tant diseases, shows, I hope, the grave character of its relation 
to man. Although its importance in this respect is being 
gradually realised in this country, it is not so widely recog- 
nised as it should be. In the United States of America it is 
proposed to change this insect’s name from the house-fly to 
the “ Typhoid fly ” ; notwithstanding certain objections to this 
name, it clearly indicates that more attention must be paid to 
preventive measures, that is, they must be reduced by the 
deprivation of suitable breeding-places. I have not discussed 
in the present paper the relation of house-flies to infantile or 
summer diarrhoea, chiefly because we are not yet certain as to 
the speciflc cause, but this disease may be included for the 
present under typhoid or enteric fever in so far as the relation 
of flies with it is concerned. 
I should like to take this opportunity of thanking those 
medical men, whose names I mention later, for the kind 
manner in which they have replied to my inquiries concern- 
ing their observations on various diseases of which they have 
special knowledge. 
