STUDIES ON FERMENTATION. 93 



obtained by the following method ; — Pour a small quantity 

 of water into a test-tube, which should then be placed slant- 

 ingly : introduce some fresh yeast into the middle part of the 

 tube, and close the tube with a wad of cotton, to prevent the 

 entrance of exterior particles of dust. In this vapour-filled 

 receptacle we shall sometimes see flakes develop. It seems 

 that Messrs. Berkeley and G. II. Hoffmann have also obtained 

 penicillium from ferment, by a similar process."* 



Why, however, should it not be admitted that penicillium 

 found under such conditions may be derived from spores of 

 that growth, adhering to the sides of the tube before it is 

 closed with the wad, or mixed with the yeast that is put into 

 the tube ? 



The facts alleged during the last few years by M. Bail, who 

 persists in his views, in spite of their apparently greater exact- 

 ness, are also far from being satisfactory.! 



M. Trecul, who is almost the only one in France, besides 

 Messrs. Ch. Robin and Fremy, to participate in these errors, 

 does not confine himself to afiirming the change of the spores 

 oi p)^nicilliiim into yeast, and vice versa; his system is a far more 

 extensive one. " According to my observations," he says, "there 

 would be the following series of changes : albuminous matter 

 changed into bacteria, or directly into alcoholic ferment, or into 

 tnycoderma ; bacteria into lactic ferment, there becoming im- 

 moveable ; lactic ferment into alcoholic ferment ; alcoholic 

 ferment into mycoclerma cerevisiw ; finally, mycoclenna cerevisice 

 into penicillium. J 



M. Trecul does not stop here. He goes on to explain the 



* Hermann Hoffmann, Etudes Mycologiqnes sur la Fermentation. 

 Botanische Zeitung and AnnaJes des Sciences Naturelles, ■4'' serie, t. xiii. 

 p. 24, 1860. 



t Communication sur VOrigine et le Developpement de queJques Cham- 

 pignons, Dantzig, 1867. 



X Trecul, Comptes rendus de V Academic, t. Ixxiii. p. l-lo4 ; Docember 

 28, 1871. 



