PABUSITIO CAUKER OF THB KAB— EOZBMA. 85 



EAB, FAKASITIC CANKEK OF.-In the summer of 

 1891, Mr. A. J. Sewell, M.R.C.V.S., called my attention to a 

 parasite he had found in the ear of a dog suffering from canker, and 

 he subsequently published a description of it in the Kennel Gazette, 

 with drawings accurately representing the creature as I saw it under 

 his microscope. Mr. Sewell named the parasite Psoroptes auricularis 

 cards, and it was undoubtedly an independent and original discovery 

 on his part. The parasite would, however, appear to have been 

 previously known, and is not a Psoropt but a Simbiot — two creatures 

 it is sufficient for the purpose of this book to say are remarkably 

 alike. They differ from the mites of mange in not burrowing or 

 tunnelling galleries under the skin, but live in colonies on the sur- 

 face, and the skin lining the passage into the ear being thin and 

 soft, they, by their bites, cause great irritation, and produce the 

 dryish brown discharge which most dog-owners must have observed 

 La cases of canker. Mr. Sewell describes these parasites as " running 

 about the skin and along the hairs in the ear, at a fairly rapid rate. " 

 They do not live on the skin of the body, or even extend their 

 wanderings to the flap of the ear. Mr. Sewell's prescription for the 

 destruction of these parasites is : Ointment of nitrate of mercury 

 (strong citron ointment), Idr. ; oil of sweet almonds, loz. ; mixed — 

 to be applied with a camel-hair pencil, ol a few drops poured into 

 the ear. The mild citron ointment of the chemist is much the same. 

 Whichever is selected, it should be used when freshly made. 



EAK, POLYPUS IMT THE. — Polypi sometimes occur in 

 the Uning membrane of the external meatus, and their removal ia 

 always best left to the veterinary surgeon. 



EAK, WAX HABBEITZK'G Iir THE.— In this case warm 

 water injections are often useful ; afterwards the ear should be care- 

 fully dried, the dog's head laid flat on one side, and a little oil of 

 sweet almonds poured into the cavity. This should be done daily 

 until the wax is softened and discharged. Or the ear may be syringed 

 with 1 part spirits of wine and 20 parts lukewarm water. After- 

 wards dry it with cotton-wool rolled round a probe or piece of 

 pointed stick. 



ECZESIA (Bed BXange). — Eczema differs from mange in being 

 non-contagious ; it is constitutional, and is not caused by parasites, 

 as is mange proper. It may be general or local, and consists of an 

 eruption of minute vesicles ; these discharge an acrid fluid, and 

 often coalesce. The skin has a scarlet appearance, often becomes 

 wrinkled, and is frequently completely denuded of hair, while there 



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