142 PRACTICAL BOTANY. 



The Torula condition may be induced in certain of the species 

 of Mucor, especially in M. racemosus (though not so readily in 

 M. mucedo), by growing the mycelium immersed in a nutritive 

 solution such as Pasteur's solution : the hyphse then become 

 partitioned off by transverse septa into short gemmae. During 

 this stage alcoholic fermentation may be effected by it. On being 

 re-exposed to the air, under other suitable conditions, the gemmae 

 may germinate and produce a normal mycelium. Observations 

 should be made on these points. 



SPORODINIA GRANDIS, Link 



V. Mitcor mucedo also reproduces itself by means of 

 zygospores, which are of such size that they may be 

 detected with the naked eye as black bodies which 

 project slightly from the substratum; but they are not 

 of constant occurrence, and may frequently be looked 

 for in vain. Accordingly it will be found more con- 

 venient and successful to study the development and 

 structure of the zygospores in an allied form, in which 

 they are produced in profusion, viz. in Sporodinia 

 grandis, Link. (= Syzygites megalocarpus, Ehr.). 



Sporodinia is a fungus which may commonly be 

 found in autumn, growing parasitically on many of the 

 larger, fleshy Hymenomycetes, especially on Russula, or 

 Boletus: it appears as a greyish or brown flocculent 

 growth, and the zygospores are of such a size that they 

 can readily be seen as reddish-brown bodies with the 

 naked eye. While a part of the mycelium ramifies in 

 the tissue of the host, the zygospores are borne on 

 aerial branches : they may thus be easily recognised as 

 brown bodies, visible to the naked eye. 



Tease out a small piece of the flocculent mycelium 



