54 



MORPHOLOGY AND CULTURE OF MICROORGANISMS 



grain, concentrated foods, such as jellies, preserves, and dried meats 

 upon which they produce green conidial areas which are later dotted 

 with bright yellow perithecia. 



Aspergillus fumigatus, Fresenius, is a green form characterized by 

 short conidiophores enlarging gradually into heads and bearing a single 

 set of sterigmata on the very apex, with chains of thin-walled green 

 spores about 3^* in diameter. This species produces a destructive 

 disease of birds known as aspergillosis. The same species is sometimes 

 reported as pathogenic to man. 



Fig. 34- Fig. 35. 



Fig. 34. — Aspergillus glaucus. a, Conidiophore showing increased diameter 

 over the vegetative cells at its base (X128); 6, sterigmata (X4S0); c, conidia, smooth 

 thick walled in this variety, other varieties are spiny (X4S0); d, perithecium(Xi28); 

 e, ascus containing ascospores (X4S0). {Original) 



Fig. 35- — Aspergillus, (i) A. fumigatus, Fres; (2) A. nidularts. i and 2 show 

 the simple sterigmata of A. fumigatus and the secondary sterigmata of A. nidulans. 

 The conidia of these species do not remain attached in ordiaary fluid mounts. 

 (Original.) ' 



* 



Aspergillus nidulans differs by having two sets of sterigmata, but 

 otherwise frequently closely resembles Aspergillus fumigatus and is fre- 

 quently mentioned as pathogenic. 



Aspergillus oryzm has been used to produce "Taka-diastase" from 

 rice in Japan. Other species produce amylase also, but in different 

 degrees. 



Aspergillus wentii, Wehmer, characterized by its long conidiophores 

 and coffecrcolored heads of conidia, is found in the soja preparation in 

 Java. 



Of other forms constantly met, Aspergillus candidus has white or 



•The unit of measurement is the micron Qi) or micro-millimeter (.001 mm.or ^1000 in.) 



