49 



an important factor in the spread of typhoid, and various intestinal 

 diseases, and to a less extent tuberculosis, and possibly other diseases. 

 Methods of control by screening and trapping, destruction of breeding 

 places, trapping out of doors during preoviposition stage. Danger as 

 a disease carrier lessened by proper sewage disposal, and by dis- 

 infection of typhoid discharge. For detailed discussion, see Howard 

 "The house-fly-disease carrier". 



Haematobia serrata, the horn-fly — Now found nearly everywhere 

 in the United States, though introduced from Europe about 1885. 

 About half the size of a house-fly and very much like it in shape and 

 color, these flies get their name from their habit of clustering about 

 the base of the horn. When feeding, puncture skin and suck blood. 

 Remain on animal day and night and by irritation and annoyance 

 cause much loss through reduced vitality, lack of growth, or loss of 

 milk. Eggs laid in freshly dropped cow manure, hatch in twenty- 

 four hours; larvae transform in four or five days into pupse which 

 remain in the ground for ten days. Preventive measures, spraying 

 cattle by means of a hand spray pump with a mixture of fish oil 

 100 parts, oil of tar 50 parts, crude carbolic acid 1 part. 



Family HIPPOBOSCIDAE, the /owse j^ies— Abnormal flies which, 

 as adults live parasitically, like lice, upon the bodies of birds and 

 mammals. Some species winged, some wingless, others winged for a 

 time and then lose their wings. The most common representative is : 



Melophagus ovinus, the so-called "sheep tick" — Reddish, wingless, 

 flattened, louse-like body, prominent proboscis, and strongly devel- 

 oped legs, with very prominent claws. Viviparous, each female 

 producing a half-dozen, more or less, full grown larvae which, attached 

 to the wool, quickly transform into seed-like brown puparia. When 

 abundant may cause death of lambs, and cause considerable damage 

 to old sheep. May be readily controlled by dipping sheep each year 

 after shearing, in any of the standard dips for lice and scab. 



Order SIPHONOPTERA 



True Fleas 



Ctenocephalus canis, the dog flea — The most common house flea 

 in this country. Closely related, if not the same species, occurs on 

 cats. 



