MICROSPORUM TARDUM 



993 



Microsporum tardum Sabouraud, 1909. 



Found by Sabouraud in cases of microsporosis capitis clinically 

 identical with the type caused by M. audouini. Differs from 

 M. atidouini by the growth being much slower and scantier, and 

 the duvet being shorter. 



Microsporum lanosum Sabouraud, 1907. 



Synonym, — Microsporon audouini var. canis Bodin, 1897. 



Commonly found in dogs. May affect man, causing a type of 

 severe tinea capitis; may also produce forms of tinea barbae and 

 tinea corporis. 



On Sabouraud's agar the growth is at first similar to M. audouini, 

 only more abundant and more downy. Later— twenty-five to 

 thirty days from inoculation — the central portion of the growth 

 becomes umbilicated, the depression being surrounded by a ring 

 of snow-white duvet, which in very old cultures may become 

 yellowish. Pleomorphism is common. 



Microsporum felineum C. Fox and Blaxall, 1896. 



Common in the cat in England, North America, and Belgium; 

 may infect man, attacking hairy and non-hairy regions of the body. 

 On Sabouraud's agar the growth is rather abundant, discoid, with 

 flattened surface, showing no furrows, and covered with a large 

 amount of grey duvet. The fungus is easily inoculable into cats, 

 dogs, and guinea-pigs. 



Microsporum minimum Le Calve and Malherbe, 1898. 



Synonyms, — Microsporon audouini var. equinum Bodin, 1896: 

 Trichophyton minimum Le Calve and Malherbe, 1898. 



Very common in foals; may infect man, giving rise to a mild 

 type of tinea corporis, which gets cured spontaneously. 



On Sabouraud's and glucose agar the growth is deeply furrowed, 

 and, in contrast to all other microsporons, duvet is absent, or, when 

 present, is very scanty, very short, and of a pinkish colour. 



Microsporum fulvum Uriburu, 1907. 



Found by Uriburu in cases of tinea capitis in the Argentine. 

 It grows very rapidly on Sabouraud's agar, the growth presenting 

 a central umbo, or projection, surrounded by a brownish powdery 

 ring. The peripheral zone of the growth is covered with white duvet. 



Microsporum pubescens Sabouraud, 1909. 



Discovered by Sabouraud in a case of tinea capitis contracted 

 in New York. It grows rapidly on Sabouraud's medium, the 

 culture being characterized by the presence of abundant but very 

 delicate silky duvet. At complete development — about thirty 

 diys from inoculation — the growth may have a flattened surface, 



63 



