FUNGI 



181 



Mould. One of these moulds, Mucor mueedo, which is very com- 

 mon on all decaying fruits and vegetables, is shown in Fig. :il7,some- 

 what magnified. When fruiting, this mould appears as a dense mass 

 of long white hairs, often over an inch high, standing erect from tin- 

 fruit or vegetable upon which it is growing. 



The life of this mucoi begins with a minute 

 rounded Bpore (a, Fig. 318), which lodges on the 

 decaying material. When the spore germinates, 

 it sends out a delicate thread which grows rapidly 

 :i- Spores of mucor; in length and forms very many blanches which 

 some germ liuit mt;. SO on permeate every part of the substance on which 

 the plant grows (//, Fig. 318). One of these threads is termed a bypha. 

 All the threads together form the mycelium of the fungus (180). The 

 mycelium disorganizes the material in which it grows, and thus nour- 

 ishes the mucor plant (Fig. :il7). It corresponds physiologically to 

 the roots and steins of other plants. 



When the mycelium is about two days old it begins to term the 

 long fruiting stalks which we first noticed. To study them, use ;i 

 compound microscope magnifying about two hundred diameters. One 

 of the stalks, magnified, is shown in Fig. 319, <t. It consists of a 

 rounded head, the sporangium, sp, supported on a long, delicate Btalk, 

 the 8porangiophore, 8t. The stalk is separated from the Bporangium 

 by a wall which is formed at the base of the sporangium. This wall, 

 however, does not extend straight across 



the thread, but it arches up into the Bpor- . V^"^v, 



angium Like an inverted pear. It is known 



iis the columella, c, Winn the sporangium 

 is placed in water, the wall immediate!] 

 dissolves and allows hundreds of spores, 

 which were formed in the cavity within 

 the Bporangium, to escape, 6. All thai is 



left of the fruit is the stalk, with the pear 

 shaped columella at its summit, 0. The 



spores which have been Bel free by the 

 breaking of the Bporangium wall are now 

 scattered by the wind and other agents. 



Those which lodge iii favorable places be- :l ' ' il poram 



, . , . . po i angium bui i luit; 



gin to grow immediately ami reproduce columella. 



the fungus. The others b i periahi 



The mucor may ttinue to reproduce itself in this way indefi- 

 nitely, bul these --pores are very delicate and usually die if they do not 

 fall on favorable ground, so thai the fungus is provided with another 



Si 



V'\ 



