SIMPLE PLANTS 



each other, it will lead to a clearer understanding of each. Both can be 

 studied only by the effects they produce, the one injurious, the other 

 beneficial. 



One may also think of several other possibilities on the part of the 

 invading organism. For example, it may live entirely at the expense 

 of its host, in which case it is a parasite ; it may live on decayed matter 

 and do little if any injury, and thus be a saprocyte, or it may actively 

 engage in killing and devouring parasitic invaders and thus be of great 

 value to its host, when it is known as a phagocyte. 



True yeasts grow by budding (Fig. 87) ; they rarely form mycelia; 

 under unfavorable conditions of growth they may form endospores. 



Oidia grow by budding and as mycelia with spore formation. (Fig. 

 102.) 



Hyphomycetes (Fig. 98) grow as mycelia with spore formation of 

 asexual or sexual origin. 



All authorities seem agreed that there is no sharp line of demarca- 

 tion between the blastomycetes and the hyphomycetes, and most of them 

 place the oidia as a transition form. 



Fig. 102. 



Oidium, showing spores 

 being cut off from the 

 tip of the branch. Such 

 spores are called conidio- 

 ipores. 



Fig. 103. Aspergillus Fumigatus. (After Brumpt. ) 



Blastomycosis (also called Saccharomycosis), is the term applied to 

 the lesions produced by a blastomyces. A variety of organisms have 

 been cultivated from the lesions, and different names have been assigned 

 to them. "It is not known if these are distinct entities. Most study of 

 this type of organism has been about Chicago. 



"There is an infection in the skin, usually remaining localized there. 



