210 DEVELOPMENT OF THE ASPERGILLALES 



(Fig. 142, C). This process is repeated again and again just 

 below each successive spore and in this way chains of spores 

 are formed. It will be noticed that many single spores are found 

 instead of a large sporangium which contains many spores as 





FIG. 142. Formation of spores or conidia in the Aspergillales : A, spore- 

 bearing hypha of Aspergillus. B, hypha of green mould, Penicillium. C, 

 one of the terminal branches of B enlarged, showing manner of spore 

 formation. 



in the case of Mucor. These spores are sometimes regarded 

 as sporangia which have become reduced in size and contain but 

 a single spore. In Aspergillus, a fungus common upon preserves 

 and upon herbarium plants that have not been sufficiently dried, 

 the spores are developed from very short branches that arise 

 from a bulbous swelling at the apex of the erect hyphae (Fig. 

 142, A). The color of the spores, as in Mucor, is the cause of 

 the characteristic blue or brown color of the fungi. These ex- 

 tremely small and numerous spores float off in the air as an 

 invisible dust and quickly germinate under favorable conditions, 

 forming new mycelia. 



The male and female gametangia are very similar, short bran- 

 ches that become closely intertwined (Fig. 143, A). The fusion 



