PRELIMINARY OBSERVATIONS. 13 



The Piiff-ballsj it was remarked, were in their first condi- 

 tion cellular, though so dusty when mature. A large group of 

 Fungi, containing multitudes of the most exquisite micro- 

 scopic objects, is distinguished by the early condition being 

 creamy, or mucilaginous. They differ in many respects from 

 other Fungi, and especially because they seem often quite inde- 

 pendent of the substance on which they are developed. One 

 species, for instance, was discovered by Schweinitz, in America, 

 growing on iron which had been red-hot only a few hours be- 

 fore. I can myself answer for the true nature of the produc- 

 tion, as 1 possess a portion of the original specimen. I have 

 seen specimens again of another species, growing on a leaden 

 cistern at Kew, from M'hich it could derive no nutriment. 

 Another was found by Sowerby, on cinders, on the outside of 

 the dome of St. Paul's. In consequence of this and of some 

 peculiarities in the substance of which they are formed, re- 

 sembling that of which certain Infusoria are composed, a very 

 excellent observer, Dr. de Bary, has lately expressed a formal 

 opinion that they are animals ; but a sufficient answer to this 

 is the fact that some of the species contain spiral vessels, and 

 have their spores surrounded by a distinct sac, exactly as in 

 an abnormal condition of Hymenangiwn (Plate 1, fig. 3, 6). 

 The most familiar example is that of the yellow, frothy, and 

 ultimately dusty substance which is so common on the tan of 

 stoves, and which is the plague of cultivators. Some species 

 of Reticularia also are so large as to attract notice, especially 

 R. maxima, which sometimes runs over cucumber-beds, over- 

 whelming everything in its path, and choking the plants. 

 Spumaria mucilago is another conspicuous Fungus of the 

 group, which is far from uncommon on the stems of grasses. 

 Most however of the species are too small to attract general 

 notice, though from the elegance of their form and brilliancy 



