310 INTRODUCTION TO CKYPTOGAMIC BOTANY. 



Rhopalomyces* a closely allied genus. In this case, however, 

 there is a little spicule which supports the spore. 



330. Moulds occur in all parts of the world, where the tem- 

 perature is sufficient to sustain their growth. They are, per- 

 haps, capable of enduring a greater range of temperature than 

 any other plants, though they could not be produced in tem- 

 peratures at which some Algse flourish. Species are seldom 

 collected by travellers, but their specimens often give evident 

 token of having suffered from their growth in the act of drying. 

 Aspergillus glaucus is esteemed when occurring in cheese ; 

 but with this exception they may be pronounced as mischievous 

 pests, of no practical use to man, except as helping in the work 

 of decomposition, and the preparation of soil for new growths. 



3. Dematiei, Fr. 



Mycelium cellular or floccose, mostly sparing. Fertile 

 threads erect, in general more or less carbonised, and conse- 

 quently rigid. Spores scattered, whorled, or collected in heads, 

 often large and septate. 



331. As the last tribe was distinguished by hyaline threads 

 of various colours, so the present is known by its dark brown, 

 approaching to black, where the tint is deep. It is rare that 

 the tint partakes decidedly of red as in (Edemium, the threads 

 of which are of a dark purple brown. Occasionally there is a 

 tint of green, verging almost always on olive. In a few cases 

 only, the threads are hyaline with dark seeds. The distinction, 



* Ajin. of Nat. Hist., N.S., vol. vii., tab. 5. Several genera occur, in 

 wliicli either single spores or necklaces of spores are produced on 

 such spicules. Rhinotrichum is an excellent example, and the same 

 structure obtains in Stachylidium diffusum, Fr., though it appears 

 to have been overlooked (Fig. 71, c). The fertile branches in their 

 young state are cystiform. Seven spicules, but sometimes a less or 

 greater quantity, soon appear on the surface, which swell into as many 

 new cysts, or sometimes by division into twice that number, covered 

 with a second more numerous set of obtuse processes, each of which 

 supports a spore. I am inclined to think that Botrytis Bassiana will 

 eventually prove to be the same thing. Moulds, above all Fungi, re- 

 quire to be traced from an early period to ascertain their history and 

 true structure. I am unable to notice every singular form amongst 

 these productions, as the volume, were I to do so, would extend far 

 beyond its prescribed limits. 



