NUTRITION. THE MACHINERY. 29 



its oxygen is to convert that glucose into alcohol. Thus 

 fermented liquors, such as beer, wine, &c., owe the alcohol 

 they contain to the temporary cutting off of the supply of 

 oxygen to the ferment, in consequence of which the glucose 

 they contain becomes converted into alcohol. 



Carnivorous Plants, Parasites. The leaves of certain 

 plants are endowed under certain circumstances with a 

 power of digesting and absorbing animal substances placed 

 in contact with them. When a minute fragment of meat, 

 for instance, is placed upon the leaf of a Drosera, or sundew, 

 the tentacle-like glandular hairs of {he plant bend over to 

 gi*asp the intruding morsel, a peculiar digestive fluid is 

 formed as a result of the contact just as the gastric juice 

 in the human stomach is secreted when food enters that 

 organ and this fluid effects the solution of the meat, the 

 nutritive solution so formed being absorbed and applied to 

 the benefit of the plant. To common observation the actual 

 gain to the plant by this method of feeding may appear 

 slight, or even none ; but the more delicate tests applied 

 by the botanist have sufficed to prove, not only that the 

 processes just mentioned really do go on, but also that they 

 are beneficial to the plant, and contribute to the formation 

 of more numerous and more robust seedlings. The 

 rationale of this mode of obtaining nutrition seems some- 

 what analogous to that in the root, where also the acid fluid 

 with which the cell wall is permeated, when it comes into 

 contact with the particles of soil, determines their solution 

 and renders them fit for absorption into the plant. Practi- 

 cally this admittedly exceptional mode of nutrition by the 

 leaf might seem of little moment, but it is probable that in 

 the future direct nutrition by this means will be shown to 



