The Molds 



49 



Reproduction is asexual and takes place through conidia 

 spores. The fruit hyphae, which are aerial, terminate in 

 rounded extremities which are known as columella, from 

 which many radiating sterigmata arise, each terminating in a 

 series of rounded spores. A sexual form of reproduction also 

 takes place through the production of ascospores. Many 

 species are known, only a few of which are pathogenic. 



Fig. 13. Aspergillus glaucus: A, A portion of the mycelium m, with 

 a conidiaphore c, and a young perithrecium F, magnified 190 diameters; 

 B and B', conidiaphore with conidia; B, individual sterigma greatly 

 magnified; C, early stage of the development of the fructifying organ; 

 D young perithrecium in longitudinal section; w, the future wall of 

 the contents; as, the screw, magnified 250 diameters; E, an ascus with 

 spores from a perithrecium, magnified 600 diameters (duBary). 



Aspergillus malignum has been found by von Lindt in the 

 auditory meatus of man. 



Aspergillus nidulans occasionally infects cattle. It is 

 pathogenic for laboratory animals, usually causing death in 

 sixty hours. The kidneys are found enlarged to twice their 

 normal size, and show small whitish dots and stripes of cell 

 infiltration containing the fungi. The heart muscle, dia- 

 phragm, and spleen may also be involved. The liver usually 

 escapes. It takes a large number of spores to infect. 



Aspergillus fumigatus. This is a widespread and not in- 

 frequently pathogenic form. Its most common lesion is a 



