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Contents 



CHAPTER III 



Ticks and Mites 



Ticks, 26; general characters, 27; mouth-parts, 27; habits, 

 27; life-history, 27; Ticks and disease, 28; Texas fever, 28; its 

 occurrence in the north, 28; carried by a tick, 29; loss and 

 methods of control, 31; other diseases of cattle carried by ticks, 

 31; Rocky Mountain spotted fever, 32; its occurrence, 32; 

 probably caused by parasites, 32; relation of ticks to this dis- 

 ease, 33; Relapsing Fever, 33; its occurrence, 34; transmitted 

 by ticks, 34; Mites, 35; Face-mites, 35; Itch-mites, 36; Harvest- 

 mites, 37. 



CHAPTER IV 



How Insects Cause or Carry Disease 



Numbers, 40; importance, 41; losses caused by insects, 41; 

 loss of life, 42; The flies, 43; horse-flies, 43; stable-flies, 44; 

 surra, 45; nagana, 45; black-flies, 46; punkies, 46; screw- worm 

 flies, 47; blow-flies, 48; flesh-flies, 48; fly larvae in intestinal 

 canal, 49; bot-flies, 50; Fleas, 52; jigger-flea, 53; Bedbugs, 54; 

 Lice, 54; How insects may carry disease, 55; in a mechanical 

 way, 55; as one of the necessary hosts of the parasite, 56. 



CHAPTER V 



House-flies or Typhoid-flies 



The old attitude toward the house-fly, 57; its present stand- 

 ing, 58; reasons for the change, 58; Structure, 59; head and 

 mouth-parts, 60; thorax and wings, 61; feet, 62; How they 

 carry bacteria, 62; Life-history, 63; eggs, 63; ordinarily laid in 

 manure, 63; other places, 63; habits of the larvse, 64; habits of 

 the adults, 64; places they visit, 65; Flies and typhoid, 65; 

 patients carrying the germs before and after they have had the 

 disease, 65; how the flies get these on their body and distribute 

 them, 66; results of some observations and experiments, 66; 

 Flies and other diseases, 68; flies and cholera, 68; flies and tu- 



