CULTIVATION. 263 



together under a proposed new genus with the name of Sclero- 

 tinia. Two or three species of Typhula, in like manner, spring 

 from forms of Sclerotium, long known as Sclerotium compla- 

 natum and Sclerotium scutellatum. Other forms of Sclerotium 

 are known, from one of which, found in a mushroom-bed, Mr. 

 Currey developed Xylaria- vaporaria, B., by placing it on damp 

 sand covered with a bell glass.* Others, again, are only known 

 in the sclerotioid state, such as the Sclerotium stipitatum found in 

 the nests of white ants in South Iiidia.t From what is already 

 known, however, we feel justified in the conclusion that the 

 so-called species of Sclerotium are a sort of compact mycelium, 

 from which, under favourable conditions, perfect fungi may be 

 developed. Mr. Berkeley succeeded in raising from the minute 

 Sclerotium of onions, which looks like grains of coarse gun- 

 powder, a species of Mucor. This was accomplished by placing 

 a thin slice of the Sclerotium in a drop of wat6r under a glass 

 slide, surrounded by a pellicle of air, and luted to prevent 

 evaporation and external influences. J 



As to the cultivation of moulds and Mucors, one great diffi- 

 cult}^ has to be encountered in the presence or introduction of 

 foreign spores to the matrix employed for their development. 

 Bearing this in mind, extensive cultivations may be made, but 

 the conditions must influence the decision upon the results. 

 Rice paste has been used with advantage for sowing the spores 

 of moulds, afterwards keeping them covered from external in- 

 fluences. In cultivation on rice paste of rare species, the 

 experimenter is often perplexed by the more rapid growth of 

 the common species of Mucor and Penicillium. Mr. Berkeley 

 succeeded in developing up to a certain point the fungus of the 

 Madura Foot, but though perfect sporangia were produced, the 

 farther development was masked by the outgrowth of other 

 species. In like manner, orange juice, cut surfaces of fruits, 



* Currey, in "Linn. Trans." xxiv. pi. 25, figs. 17, 26. 



+ Berkeley, "On Two Tuberiform Veg. Productions from Travancore," in 

 "Trans. Linn. Soc." vol. xxiii. p. 91. 



J Berkeley, " On a Peculiar Form of Mildew in Onions," " Journ. Hort. Soc." 

 vol. iii p. 91. 



