496 



LIFE-HISTORIES 



upon the surface of some nutrient medium germinates by 

 sending out one or more projections (Figs. 325, 3), and these 

 finding abundant food available elongate and branch indef- 



FiG. 31^4. — Pin-mold {Mucur Muccdo, Pin-mold Family, Alucoracea:). 

 Plant showing the much-branched horizontal mycelium from which 

 arise pin-like vertical hyphs (a, h, c, of different ages) that eventuall>' 

 develop dust-spore-cases at the tip. Somewhat magnified. (Zopf.) 



Fig. .325. — Pin-mold. 1, dust-spore-case, viewed as if cut vertically, 

 showing the tip of the vertical hypha (c) projecting into the spore-case; 

 the spore-case w-all (???) : and the numerous dust-spores (sp), ^i^\ 

 '2, same from which tlie dust-spores have been shed. 3. germinating 

 dust-spore, '-;"■. (Brefeld.) 



initely so long as the conditions are favorable. Soon there 

 may be as complex a system of branches as that in Fig. 324. 

 A fungus thread is termed a hypha .^ The mass of hypha* 

 forming the vegetative part of a fungal thallus constitutes 

 ' Hy'plui < (!r. lu/jihc, a web. 



