162 THE BLUE-BOTTLE-FLY. 



TSE-FLY {Glossina morsitans) ^ which is said to be so danger- 

 ous that whole regions in Africa are uninhabitable during 

 the season in which they are numerous. The mortality 

 caused hy them is no doubt due to a disease disseminated by 

 their attacks. Bruce, in his travels to discover the source of 

 the Nile, in 1790 first figured this insect, and a copy of it is 

 shown in fig. 134, while a more modern one is also given 

 to the left. 



He gives in the books published by him a very interesting 

 account of its mode of life, and a still more interesting his- 

 torical sketch of the changes produced hy it in the political 

 history of the countries in which it abounds. 



THE BLUE-BOTTLE-FLY. 



( CalUphora vomitoria Linn.), 



This beautiful fly, beautiful in colors but not in manners, 

 is known to everybody. It can not be classed as a parasite, 

 or as infesting man and beast. It is very frequently found 

 in our houses, usually trying to run its head through the 

 glass of our windows, and as constantly complaining about 

 the hardness of the latter by a deep humming sound. But 

 when we ask those in charge of our eatables they will com- 

 plain bitterly about this insect which loves meat of all kinds 

 and is very apt to spoil the same in more than one way. It 

 is shown in fig. 135, plate XII. 



THE HORN-FLY. 



{Ilcematobla serrata R. Desv.). 



This insect is a recent acquisition, and one we could well 

 do without. It reached this side of the Atlantic coast, ac- 

 cording to Prof John B. Smith, the well-known entomolo- 

 gist of New Jersey, either in 1886 or in 1887, and soon 

 spread westward. In 1892 the writer noticed it in large 

 numbers in Otter Tail County-, and was told that it had 

 there troubled cattle for some 3'ears. Mr. L. A. Foote, of 

 Worthington, Minn., a very careful observer, told me very 

 late in the fall of 1895, that it had been common in that 

 vicinity long before 1886, and to demonstrate that he knew 



