Mucor Corymbifer, Lichtheim. 



V 



ORIGIN. Is of rare occurrence, and was found as a con- 

 tamination on bread- gelatin plates and on white bread 

 which was kept at the body temperature. It has been 

 found in the ear-passages of man. It is probable that this 

 same species has been found in a case of generalized 

 mycosis. 



COLOR. The mycelium, spores and sporangia are color- 

 less. 



MYCELIUM. Loose, wavy, branching, slender mycelial 

 threads which form a white cotton-like mass an inch or 

 more in height. 



FRUIT-ORGANS. The fruit-hyphas branch forming clusters 

 or corymbs which terminate in spherical or pear-shaped 

 sporangia. Within these are the colorless, oval or elongated 

 spores, which are about 3 P. long and 2 // wide. 



GROWTH. Rapid and extensive. 



Bread-flasks In the incubator it forms a white, elevated, cotton- 

 like growth which soon fills the flask. On potato a similar cotton-like, 

 tall growth develops. 



TEMPERATURE. Grows slowly at the ordinary tempera- 

 ture; best at 37. 



PATHOGENESIS. Intravenous injection of the spores into 

 rabbits produces death in 3 to 4 days. The kidneys, 

 mesenteric glands and Peyer's patches contain mycelial 

 masses. The Peyer's patches are swollen and ulcerated. 

 Intraperitoneal injections produce the same results. Dogs 



are immune. 



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