Diseases of the Skin. 247 



scissors, after which the embedded portion may be re- 

 moved by forceps, or a drop of turpentine will answer the 

 purpose. 



Vegetable Parasites. — Of this class two are common 

 to canine animals. They are true fungi in nature, attach 

 themselves to the epithelium or scarf skin, as well as the 

 hairs proceeding from it, and are readily detected under 

 an ordinary microscope. They pr^ail in damp, dark, 

 and ill-drained places, and young animals are especially 

 susceptible of attack ; but in all cases want of condition 

 and general cleanliness predisposes the animal to their 

 effects. They are also communicable from other species 

 of animals to the dog, and he may convey them to others 

 besides his own, or even to mankind by contagion alone. 

 This may be mediate or immediate, and from the nature 

 of the spores, it is believed that the air may act as a 

 suitable medium. After being deposited on the skin, 

 the process of incubation commences, and occupies from 

 eight or ten to fourteen days, when they produce a 

 colony of spores, and from the circumstance of their 

 common arrangement in the form of a circle, the disease 

 they produce is familiarly known as Ringworm. 



Tinea Tonsurans, or Ringworm, is occasionally seen 

 in the dog. It occurs in circular patches, destitute of 

 hair, except a few which by the action of the fungus, are 

 broken and lifeless, standing among the enlarged cells, 

 and projecting irregularly. Growth is on the external 

 margin ; thus, the skin first affected is left smooth, and 

 covered with glistening scales, or an aggregation forming 

 a grey crust, each of which contain the spores of the 

 fungus Achorion kbertii, or Trichophyto7t tonsurans. 

 Constant cleansing with " Sanitas " Soap and warm water, 

 and subsequent dressings with the tincture of cantharides, 

 or iodine ; dilute mineral and acetic acids, mercurial, or 

 nitrate of silver ointment, tincture of iron, &c. &c., usually 

 effect a cure. The disease is liable to be mistaken for 

 Herpes circinatus^ or vesicular ringworm, a form of local 

 eczema common in young dogs as a result of indigestion, 

 teething, &c., on the cessation of which it disappears. 



Tinea Favosa, or Honeycomb Ringworm^ variously 



