DISEASES OF THE SKIN. 345 



TICKS IXODES. 



There are several species of ticks that attach themselves to cattle. 

 The most coinmoii in this country is the Boopliilus bovis. (Plates XLIV.) 

 They are most numerous on uncultivated land, prairies, and woodland. 

 They attach themselves to cattle on the thighs, flank, and neck, where 

 they fill themselves with blood and then drop to the ground. They 

 bore into the skin and cause considerable irritation of the parts. They 

 may be destroyed by the application of oil or grease which kills them 

 by occluding their breathing pores. When they are carelessly pulled 

 oft' by hand the head sometimes bre aks off and remains in the skin, 

 causing a suppurating sore and possibly septic infection of the animal. 



FLEAS PULEX IRRITANS AND SAROOPSYLLA PENETRANS. 



The Pulex irritanSj the common flea, penetrates the cuticle with a pair 

 of very fine sharp lancets attached to its head, and draws blood from the 

 animal. They become annoying to cattle when they are present in 

 great numbers, and cause a diminution of milk. 



The Sarcopsylla penetranSj the chigre, met with in some of the west- 

 ern States, burrows beneath or within the skin, and deposits its eggs, 

 causing the animal to rub the parts. A small vesicle may form, suc- 

 ceeded occasionally by the formation of a small ulcer. 



Treatment. When fleas or chigres cause much annoyance to cattle it 

 can be prevented by moistening their skin every morning with tobacco 

 juice or carbolic-acid water 1 ounce of the acid to 2 quarts of water. 



FLIES AND MOSQUITOS. 



These may become dangerous to cattle in sections where malignant 

 anthrax prevails, as they may be the carriers of poison from the diseased 

 or dead animal to the healthy one. 



The tsetse fly (Qlosnina morsitansj of Africa is very destructive to 

 cattle, their sting causing death in many cases. Maggots hatched from 

 the eggs deposited by flics upon wounds frequently are very annoying 

 to the animal, and retard the healing process. The maggots from the 

 screw-worm fly (Lucillia maccllariaj burrow in wounds and cause 

 increased inflammation, and have been known to cause the death of 

 cattle. When maggots or screw worms appear on wounds of the skin, 

 be they deep or superficial, no time should be lost in getting rid of them. 

 The application of turpentine or earboli/.ed water 1 ounce to a pint 

 should \tc used to destroy the vermin, and the wound afterward cov- 

 ered with tar to keep the flies away. 



RINGWORM TINEA TONSURAN8 AND TINEA FAVOSA. 



Ringworm in an affection of the skin, due to a vegetable parasite. 

 Tinea tomtnrang is due to the presence of a minute or microscopic fun- 

 gus the Trichophyton t<>iixitrnnn. It affects the hair awl the epidermic 



