MORPHOLOGY AND CULTURE OF MICROORGANISMS. 



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. 



Aspergillusnidulans differs by having two sets of sterigmata, but other- 

 wise frequently closely resembles Aspergillus fumigatus and is fre- 

 quently mentioned as pathogenic. 



Aspergillus oryza has been used to produce " Takadiastase " from rice 

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



FIG. 7. FIG. 8. 



FIG. 7. Cladosporium herba^um (r\ FIG. 8. Spores FIG. 9. Fusarium 

 showing the forms of conidiophores and of Alternaria sp. from decaying potato, 

 conidia which are very common upon (Original.) a, spores showing cur- 



laboratory culture media. (Original.) vature and septa; b, ger- 



mination of spores; c, 

 development of spores 

 in petri-dish culture; d, 

 mass of spores as found 

 in culture. (Original). 



Aspergillus wentii, Wehmer, characterized by its long conidiophores 

 and coffee-colored heads of conidia, is found in the Soja preparation in 

 Java. 



Of other forms constantly met, Aspergillus candidus has white or pale 

 cream fruiting surfaces, Aspergillus flavus produces several shades of 

 yellow and green, Aspergillus ochraceus, ocher or tan. 



Much confusion is still found in the literature of this genus, so that 

 frequent references to the activities of particular species are difficult or 

 impossible to verify. 



CLADOSPORIUM (AND HORMODENDRON). The species of Clado- 

 sporium occur frequently in cultures of decaying vegetable matter, of 

 milk and cream, or butter. The colonies liquefy gelatin. Both mycelium 



*The unit of micro special measurement is the microm (p) or micro millimeter (.001 m.m. 

 or 1/25000 in.) 



