LIVING MATTER IN "PROTOPLASMS 



43 



necting bridges being no longer visible, even with the greatest magnifying 



powers. 



The essential oidia of yeast are, as is well known, mainly oblong 



bodies, the majority of which contain a large central vacuole. High ampli- 

 fication shows that the outer shell represents 

 a usually homogeneous shining, yellow ring, 

 thickened at one pole of the oidium. Within 

 the shell, granules are present, each of which 

 is separated from the other contents by a light 

 seam, and connected with the shell by minute 

 threads. The surface toward the vacuole is 

 either smooth or covered by granules, a part 

 of which projects into the vacuole. The thick- 

 ened portion of the shell is not seldom per- 

 forated by smaller vacuoles, each surrounded 

 by a layer of the yellowish, shining substance. 

 In the interior of the vacuole, isolated minute 

 granules may be found in active motion, while 

 smaller vacuoles contain a varying number of 

 granules, connected among each other and with 

 the shell by finest filaments. (See Fig. 11.) 



Oidia without vacuoles have always a rela- 

 tively thin shell, and contain a number of 

 granules of different sizes, which, without ex- 

 ception, are united. Only the yellowish, shin- 

 ing substance of the shell and the granules 



become dark violet from the solution of chloride of gold; all other parts 



remain uncolored, or, at most, become only pale violet. 



In fermenting wine, I met with a great number of small, free granules, 



with short, rod-like formations (bacteria), and the round or oblong oidia. 



Numerous oidia form chains of two or more members, the single links of 



which are united by short, broad 



bridges. Occasionally a small bud 



is attached directly, with a broad 



basis, to a larger oidium. High 



magnifying power shows that here 



vacuoles are less numerous, and 



of markedly smaller size, than in 



beer-yeast. Each oidium is bounded 



by a yellowish, shining shell, per- 

 forated only at the union with its 



neighboring oidia, and containing 



in its interior a varying number of 



granules of different sizes, all con- 

 nected by delicate threads. The 



granules show the same refraction 



FIG. 11. OIDIUM OF YEAST. 



a, homogeneous granules, partly 

 isolated, partly in shape of chains ; 

 b, oidia with large vacuoles, whose 

 walls are either compact or gran- 

 ular, or traversed by minute vacu- 

 oles ; c, oidium devoid of a vacuole, 

 its living matter in net-like ar- 

 rangement, the points of intersec- 

 tion being the granules. Magnified 

 1200 diameters. 



FIG. 12. OIDIUM OF FERMENTING 

 WINE. 



a, isolated oidia ; b b, oidia in chain-like con- 

 nection. In all these the living matter is arranged 

 net-like ; the shell, being also a formation of living 

 matter, looks homogeneous, and is perforated 

 where the uniting bridges inosculate. Magnified 



and color as the shell, while the 1200 diameters, 

 threads between the single gran- 

 ules and the different oidia are colored gray. Smaller buds and smaller 

 isolated oidia are almost always compact, yellowish, shining, and apparently 

 without structure. (See Fig. 12.) 



