262 Prof. H. M. Ward. The " Ginger-beer Plant," [Dec. 17, 



It occurs as jelly-like, semi-transparent, yellowish-white masses, 

 aggregated into brain-like clumps, or forming deposits at the bottom 

 of the fermentations, and presents resemblances to the so-called 

 Kephir grains of the Caucasus, with which, however, it is by no 

 means identical. 



He finds that it consists essentially of a symbiotic association of a 

 specific Saccharomycete and a Scliizomycete, morphologically comparable 

 to a Lichen, but, as met with naturally, invariably has other species 

 of yeasts, bacteria, and mould-fungi casually associated with these. 



He has successfully undertaken the separation of the various forms, 

 and groups them as follows : 



1. The essential organisms are a yeast, which turns out to be a 

 new species allied to Saccharomyces ellipsoideus (Reess and Hansen), 

 and which he proposes to call S. pyriformis ; and a bacterium, also 

 new and of a new type, and named by him Bacterium vermiforme. 



2. Two other forms were met with in all the specimens (from 

 various parts of the country and from America) examined Mycoderma 

 cerevisice (Desm.) and Bacterium aceti (Kiitzing and Zopf). 



3. As foreign intruders, more or less commonly occurring in the 

 various specimens examined, were the following : 



at. A pink or rosy yeast-like form Cryptococcus glutinis (Fresenius.) ? 



ft. A small white aerobian top-yeast, with peculiar characters, and 

 not identified with any known form. 



<y. The ordinary beer-yeast Saccharomyces cerevisice (Meyen and 

 Hansen). 



B. Three, or probably four, unknown yeasts of rare occurrence. 



e. A bacillus which forms spores, and liquefies gelatine with a 

 greenish tinge. 



". A 4 large spore-forming bacillus, which also liquefies gelatine. 



VJ and 9. Two^-perhaps three other Schizomycetes not identified. 



i. A large yeast-like form which grows into a mycelium, and turns 

 out to be O'idium lactis (Fresenius). 



*:. A common blue mould Penicillium glaucum (Link). 



X. A brown " Torula "-like form, which turns out to be Dematium 

 pullulans (De Bary). 



fi. One, or perhaps several, species of " Torula " of unknown 

 origin and fates. 



Of these forms, the author has succeeded in cultivating and 

 examining very thoroughly all but those under and fi in the fore- 

 going list. 



Saccharomyces pyriform-is (n.sp.)is a remarkably anaerobian bottom 

 yeast, forming spores, and developing large quantities of carbon 

 dioxide, but forming little alcohol. It has also an aerobian form 

 veil form of Hansen in which the rounded cells grow out into club- 

 shaped or pyriform cells, whence the proposed specific name. It inverts 



