AFFECT lOXS CAUSED BY VEGETABLE PARASITES 475 



was cured spontaneously in three weeks; in the case described by Schnei- 

 der it was necessary to use a oU per cent, sohition of balsam of Peru in 

 alcohol, to destroy the parasites. 



The Filaria immitis and Filaria medinensis are found encysted in 

 the subcutis. The embryos of the former are found in the blood and 

 also in the connective tissues in the encysted form, and it may also be 

 found free. The latter, Filaria medinensis or guinea worm, is found on 

 the west coast of Africa and Arabia, and produces abscesses and tumefac- 

 tions in the man and the dog. 



The treatment is simply cleanliness. 



Cutaneous Affections which are Caused by Vegetable Parasites. 



We know at the jDresent day of two skin diseases in the dog which 

 are ascribed to the presence of vegetable parasites. These are favus 

 and herpes. These ectophytes belong to the filiform fungi class (hypho- 

 mj'cetes) and may be simple or ramified, membranous or non-membran- 

 ous, double contoured, cellular threads (hyphae), which become mixed 

 in their growth and form a real fungous bed or fungous turf (mycelium). 

 These fungous growths produce at their ends and at the point of their 



Fig. 172. — Fa\'U3 spores, magnified 450 times, (von Diiben.) 



short side branches bead- or string-like spores, uniting and ligating each 

 other, which are considered as sexual or multiplying organs. We 

 cannot make a strong distinction between the fungi of favus and those 

 of herpes, but there is a difference, as is seen in the disease in its local 

 form, and we have given a description of both. 



1. Favus. — This fungus is called achorion Schonleinii, and is devel- 

 oped upon the skin, between the epidermic layers in the hair-follicles, 

 and also in the hair itself, and the secreting tissues of the claws. It is 

 very rare and generally affects young animals. The determination of 

 the fung-us is the same method followed in trichophyton. It may he 

 transmitted to the cat, horse, rabbit, mouse, and human beings, causing 

 a characteristic skin affection. 



Clinical Symptoms. — Favus is found in special regions of the body, 



