FUNGI. 189 



"VVe range by the side of these, the fungi known as 

 mushrooms, toadstools, puff-balls ; and also a large num- 

 ber of microscopic plants, forming those appearances which 

 are referred to generally under the terms of mouldiness, 

 mildew, blight, smut, dry-rot, &c. It is well known that 

 fruit-preserves are very liable to be attacked by the com- 

 mon bead-mould (No. 3, tig. 104); which no care employed 

 in completely closing the mouths of the jars can prevent. 

 It is to be remarked, however, that they are much less 

 liable to suffer in this way, if not left open for a night 

 before they are tied down: and this fact induces us to 

 believe that the germs of the mould sow themselves before 

 the jar is covered. Some kinds of cheese derive their 

 flavour from the quantity of a fungous growth which 

 spreads through the mass whilst it is yet soft. This appears 

 to owe its origin to a damp atmosphere, with diminution 

 of light ; which conditions are especially favourable to the 

 development of these bodies. 



The power of reproduction of the vegetable mould-plant, 

 mucor, is so great, that extensive tracts of snow are sud- 

 denly reddened by the Gory-dew, Protococcus nivalis (red- 

 snow) of the northern regions. That the Bed-snow plant 

 consists of a cellular or filamentous tissue, may be easily 

 ascertained by means of a microscope of even moderate 

 powers ; and one of a higher power demonstrates that the 

 filaments are nothing more than cells drawn out. Some- 

 times, as in the genus Uredo, the cells are spheroidal, 

 having little connection with each other; each cell con- 

 taining propagating matter, and all separating from each 

 other in the form of a fine powder when ripe. In plants 

 of a more advanced organisation, as the genus Monilia, 

 the constituent cells are connected in series which preserve 

 their spherical, and also contain their own reproductive 

 matter ; while in such plants as Aspergillus (fig. 104, No. 2 ), 

 the cells partly combine into threads forming a stem, and 

 partly preserve their spheroidal form for fructification. It 

 is probable, however, that in all fungi, and certain that in 

 most of them, the first development of the plant consists 

 in what we here call a filamentous matter which radiates 

 from the centre formed by the space or seeds ; and that all 

 the cellular spheroidal appearances are subsequently deve- 



