STUDIES ON FERMENTATION. 71 



must of acid and sugared fruits — especially in filtered 

 grape raust. Its dimensions varied from 1 to li, or 

 2, 450tlis of a millimetre.* 



Fig. 11. 



ccc. — " Low " yeast, of a type resembling that existing in other 

 preparations fermenting in tlie room. 



ddd. — Enlarged, distended spores of mucor racemosns. These 

 are scarce, and have an old appearance. We shall come 

 to them again in a subsequent chapter, where we shall 

 explain their real significance. 



eee. — Short vibrios, occurring either contracted or not near 

 the middle. Some were motionless, others vibrating to 

 and fro and executing other movements. These forms 

 belong to the butyric and lactic ferments shown on 

 Plate I. 



* This small ferment is very curious, although it scarcely affects 

 industrial fermentation. It was first described in 1862. (Pasteue, 

 Bulletin de la SocietS chimique, 1862, page 67, and following : Quelques 

 faits nouveaux au sujet des levures alcooliques.) It has since been described 

 by Dr. Eees under the name Saccharomyces apiculatus. (Dr. Eees, 

 Leipzig, 1870 : Sur les champignons de fermentation alcooliques. See also 

 Dr. Engel, These pour le Doctorat, Paris, 1872.) If we carefully filter 

 some grape must at the time of vintage, we may be sure that we shall 

 see it appear in the clear liquid at the bottom of our vessel, without 

 intermixture with any other ferment. 



Should we not filter the must this ferment will appear all the same, 

 but it wiU soon become associated with another, thicker in appearance 

 and more elongated, which also is one of the ferments peculiar to the fer- 

 mentation of grape must. 



