45,6 



Prof. H. Marshall Ward. On Pure Cultures 



to be capable of vigorously germinating by cultures in hanging drops 

 and the whole series linked up and aerated. The growth of these 

 seedlings in the moist air-current was very satisfactory, the plants 



FIG. 1. 



Diagram showing arrangement of tubes for pure cultures of 

 text here shown connected up for aeration. Eeduced. 



A = glass jar. B = cotton-wool satxirated with liquid. C = liquid reservoir 

 containing nutritive culture solution, through which air bubbles pass 

 D and d = caoutchouc stoppers pierced by glass tubing. EE = caoutchouc 

 tubing. F = seedling with its roots in B and its leaves in air. Q- and y = 

 arrows showing direction of air current, x andy = glass tubes. 



having a deep rich green colour, though the leaves were short, and the 

 results, as shown in the following Table III, were very instructive. 



In this series the liquid employed was the normal Knop's mineral 

 solution ( + ), so well known as used in water-cultures. The tubes were 

 charged with this before sterilisation, enough being put in to wet the 

 cotton-wool plug (B), and fill the reservoir (C), the side-tube y being 

 fused at its pointed end during sterilising. 



