TBICHOPHYTONEAE 543 



Microsporum Audouini var. macrosporium Craik, Brit. Med. Jour. 1: 672, 

 673, 1921. 



Producing tinea tonsurans mierosporica and herpes circinatus in both 

 children and adults. Originally described from the dog, where it produces 

 dry, scaly lesions without vesicles or pustules; spontaneous inoculation very 

 frequent among experimental animals and experimental inoculation easy, 

 either by implanting infected hairs or from cultures. The guinea pig is the 

 animal of choice. Pleomorphic strains variable in virulence, the older strains 

 inoculable with difficulty or not at all. Very common in Tomsk, Siberia, 

 Western Russia, Bessarabia, Southern Hungary (on the right bank of the 

 Danube, not in Szeged), St. Gall, Switzerland; occasional or rare in Northern 

 Italy, Bavaria, France, Montreal, Canada, Boston, Mass., Sao Paulo, Brazil, 

 Buenos Aires, Argentina, and Australia. 



Closterospores abundant, several celled, 5-7 (-12) celled, 50-75 x 15-25/a, 

 central cells broader than long, those toward the end isodiametric or longer 

 than broad, very thick-walled, cutinized and covered with long asperities. 

 Chlamydospores intercalary, aleurospores occasional, pectinate hyphae present. 



Colony similar to M. Audouini at first, but more velvety and growth more 

 rapid, with a glabrous and powdery central area as in M. felineum; then form- 

 ing a loosely woven zone about the center (even more conspicuous on wort 

 agar). At 25 days, the center is umbilicate, the woolly layer elevated about 

 4 mm. and 1 em. wide, remaining snow white when old ; margin with immersed 

 rays, from which rises a short grayish velvet ; colony, 9-10 cm. in diameter. 

 On Sabouraud glucose agar, the woolly portion is irregular and the immersed 

 rays are yellowish. On Griitz agar, center and reverse reddish, sometimes with 

 concentric rings ; on peptone, woolly, with more or less concentric rings, bluish 

 brown. On potato, colony at first yellowish then reddish brown, smooth, finally 

 covered with a white velvet which masks the red color, suggesting M. Audouini 

 but double the size. On Pollacci agar, similar to that on Sabouraud maltose 

 agar but more yellow. On gelatin, growth slow, velvety, liquefaction only 

 after 3 weeks or a month. Pleomorphism may develop as a Avhite circular 

 disc of velvet or a radiating plaque immersed in the medium with the surface 

 smooth, humid, and brownish, or the colony may be rough with coarse echinu- 

 late tufts, the humid form being the least stable. 



Microsporuin flavescens Horta, Mem. Inst. Oswaldo Cruz 3: 301-308, PI. 

 17, 1912. 



Sahouraudifes flavescens Ota & Langeron, Ann. Parasitol. Hum. Comp. 1: 

 327, 1923. 



Producing tinea capitis mierosporica in children, Brazil. 



Very close in microscopic characters to M. canis and especially to M. 

 fulvum. 



On Sabouraud agar, growth rapid, reaching 4 cm. in 2 weeks, with slight 

 central depression and 4-5 furrows, which may disappear, reddish yellow. 

 Pleomorphism beginning in about 2 weeks. Cultural characters also given for 

 carrot, potato, etc., which are not strikingly different. 



