379 



present an eccentric spherical cavity ; this cavity, however, is 

 not the true cell-cavity, but a mere vacuole in the protoplas- 

 mic contents. Its size is very various ; it is sometimes barely 

 visible under the highest powers, while, in other instances, it 

 occupies nearly the whole of the cell. By the action of iodine 

 the protoplasm is turned dark-brown, and the cell-membrane 

 is then rendered apparent. There is no distinct indication of 

 a nucleus ; and authors who have described a manifest nucleus 

 have evidently mistaken for this body the vacuole, already 

 described, in the protoplasm. If a nucleus exist, it is probably 

 concealed in the thick opaque protoplasm. In some instances 

 the contents of the cell appeared broken down into a multi- 

 tude of detached granules ; the cell-wall was then very visible 

 without the aid of iodine ; this condition was probably con- 

 fined to dead cells. 



In an example of "spent wash," the residuum which re- 

 mains after the distillation of the fermented wort, the micro- 

 scope showed that the solid matter was almost exclusively 

 composed of ferment-cells and Bacterium filaments ; the cells 

 retained their spherical figure, but their contents presented 

 the granular condition just described. The filaments appeared 

 unaltered. 



Dr. Apjohn read a paper on the nature and relative pro- 

 portion of the alkalies occurring in the granite of the vicinity 

 of Dublin. 



A paper was read at a recent meeting of the Academy, by 

 'Sir Robert Kane, which communicated the results of some 

 analyses, made under his direction, of waters from Ticknock, 

 on the slope of the Dublin mountains. From this communi- 

 cation it appeared, that these waters included a large amount 

 of alkaline silicates, but that the proportion of potash present 

 was very small compared to that of the soda, their relative 

 quantities being very nearly represented by the numbers 1 

 and 13. 



