548 TRICHOMYCETES, ACTINOMYCETES, HYPHOMYCETES 



color, other members of the group exhibiting black, brown and other 

 colored colonies. 



Rabbits, guinea-pigs and pigeons are susceptible to infection with 

 Aspergillus fumigatus. The lesions produced resemble tubercles some- 

 what on superficial examination, but microscopic examination always 

 reveals the mycelium and spores. 



Sporotrichosis. The disease known as sporotrichosis was first 

 described by Schenck 1 and later by Hektoen and Perkins. 2 The 

 latter observers named the causative organism Sporothrix (Sporo- 

 trichon) schencki. 



Usually sporotrichosis runs a chronic course, characterized by 

 small discrete nodules in the subcutis, which at first are hard and 

 inelastic, indolent and resemble multiple disseminated gummata. The 

 lesions progress slowly and after some time soften, break through the 

 skin and discharge a slimy, serous, yellowish pus. The skin around 

 the nodules is not usually greatly indurated and there is little pain, 

 febrile reaction or constitutional disturbance. Not infrequently 

 regional lymph channels become ^thickened with a few gumma-like 

 nodules at irregular intervals, which break down and ulcerate. The 

 lesions resemble syphilitic gummata, or, occasionally, tuberculous 

 ulcerations. Rarely the disease may be acute with fever, emaciation 

 and prostration and sporotrichic nodules form on mucous surfaces 

 in the peritoneum, the lungs or kidneys. The Wassermann reaction 

 is negative and neither Treponemata nor tubercle bacilli are found in 

 uncomplicated cases. 



The organism develops readily upon ordinary culture media which 

 have an acid reaction. Material for inoculation is best obtained 

 from a softened but unopened nodule. The colonies grow slowly as 

 small plaques which develop into white fluffy masses that become 

 brown after prolonged cultivation. Secondary transfers to artificial 

 media develop much more rapidly. Many strains grow better at 

 room than at body temperature. 



The organism as seen in the pus consists almost exclusively of 

 oval spores measuring from 2 to 4 microns in diameter and from 3 to 

 6 microns in length; they are frequently collected in groups or masses 

 of from 3 to 30 or more, at the ends of the filaments. They are Gram- 

 positive. The mycelia are found in cultures as filaments about 2 

 microns in diameter and from 20 to 40 microns long. 



1 Johns Hopkins Hosp. Bull., 1898, ix, 286. 



2 Jour. Exp. Med., 1900, v, 77. 



