THE SUNDEWS. 29 



\Vc may well assume, as experiments justify the 

 assumption, that the acidulated secretion, which is 

 discharg-ed over the insect from the inflected glands, 

 aids in the digestion by the plant of this animat 

 food. It is abundantly certain that all these pheno- 

 mena, the sensibility, or irritability of the tentacles 

 when touched, their power of closing over the object 

 on the leaf, the increase of its viscid secretion, and 

 the acquisition of acid properties, are not performed 

 without a purpose, and that purpose appears to be 

 the capture of animal food, its digestion, and ultimate 

 absorption b}^ the plant. 



There can be no doubt that the glands of the leaf 

 do really possess the power of absorption, which ma}' 

 be tested by placing upon them small quantities of 

 such substances as carbonate of ammonia, the absorp- 

 tion of which causes a change of colour consequent 

 upon the aggregation of their contents. It may be 

 assumed also from the fact that the tentacles remain 

 closed longer over an object which contains soluble 

 nitrogenous matter than over one which does not. The 

 sundew has very delicate roots, which are scarceh- 

 more than suckers for obtaining moisture which the 

 plant requires in great abundance. As Mr. Darwin 

 observes, " a plant of sundew with the edges of its 

 leaves curled inwards, so as to form a temporary 

 stomach, with the glands of the closely inflected 

 tentacles pouring forth their acid secretion, which 



