STRUCTURE, DEVELOPMENT, AND BIONOMICS OF HOUSE-FLY. 349 
II. Distribution. 
Musca domstica is probably the most widely distributed 
insect to be found ; the animal most commonly associated with 
man, whom it appears to have followed over the entire globe. 
It extends fi’om the sub-polar regions, where Linnaeus I’efers 
to its occurrence in Lapland, and Finmark as “ rara avis in 
Lapponia, at in Finmarchia Norwegias integras domos fere 
replet,” to the tropics, where it occurs iii enormous numbers. 
Referring to its abundance in a house near Para in equatoral 
Brazil, Austen (1904) says: “At the mid-day meal they 
swarmed on the table in almost inconceivable numbers,” and 
other travellers in different tropical countries liave related 
similar experiences to me, how they swarm round each piece 
of food as it is carried to the mouth. 
In the civilised aud populated regions of the world it occurs 
commonly, and the British Museum (Natui’al History) collec- 
tion and my own contain specimens from the following 
localities. Certain of the localities have, in addition, been 
obtained from lists of insect faunas : 
Asia. — Aden; North West Provinces (India); Calcutta; 
Madras; Bombay (it probably occurs over the whole of 
India); Ceylon; Central China; Hong-Kong ; Shanghai; 
Straits Settlements ; Japan. 
Africa. — Port Said; Suez; Egypt; Somaliland; Nyassa- 
land ; Uganda; British E. Africa; Rhodesia; Transvaal; 
Natal; Cape Colony; Madagascar; Northern and Southern 
Nigeria; St. Helena; Madeira. 
America. — Distributed over North America; Brazil; 
Monte Video (Uruguay); Argentine; Valparaiso; West 
Indies. 
Australia and New Zealand. 
Europe and the isles of the Mediterranean; it is especially 
common in Cyprus. 
Not only is this world-Avide disti’ibution of interest, but its 
distribution in our owu country is noteworthy. From observa- 
tions that I have made during a number of years in town and 
