MOLDS AND YEASTS" AND' DISEASES CAUSED BY THEM 239 



Aspergillus Glaucus. — This is very widely distributed in 

 nature, occurring on fruits, ftioist bread and other food substances 

 and very frequently as a contamination in laboratory cultures. 

 The aerial spore-bearing hypha (conidiophore) is erect, about 

 I mm. long, swollen at the end to a diameter of 20 to 401X. On 

 the surface of this spherical head are numerous closely packed 

 spore-bearing sterigmae, each of which bears at its tip a chain of 

 spherical spores (conidia) which 

 are budded off from it. The 

 conidia are gray to olive green 

 in color. Ascospores are also 

 produced, grouped together as 

 yellow masses, called perithe- 

 cia, on the surface of the 

 medium. The mold is not 

 pathogenic. Probably a con- 

 siderable number of different 

 species have been included 

 under this name. 



Aspergillus Fumigatus. — 

 The growth of this mold is at 

 first bluish and later grayish-green. It is widely distributed. The 

 sterigmae are unbranched, thickly set on the swollen end of the 

 spore-bearing hypha. The conidia measure 2.5 to 2,1^. The for- 

 mation of ascospores has also been observed. Aspergillus fumi- 

 gatus plays a part in the heating of hay and sprouting barley, 

 and is the most common of the pathogenic aspergilli. It infects 

 doves and other birds naturally, sometimes causing veritable 

 epidemics, and the disease has been observed iil bird fanciers, 

 in whom it runs a clinical course very similar to that of pulmonary 

 tuberculosis. Fragments of the mycehum are found in the spu- 

 tum. Doubtless the human disease is contracted from the birds 

 in these cases. This mold has been found as the apparent cause 

 of inflammation in the auditory canal in a large number of cases 

 and in the nasal fossae in a few instances. Various other mammals 



Pig. 93. — Aspergillus fumigatus from the 

 lung of a parrot. (After Plaut.) 



