342 • ROEIDULA. Chap. XV. 



secretion being readily withdrawn from the glands ; so 

 that, when an insect comes into contact with a drop, 

 it is able to crawl away, but soon touches other drops, 

 and then, smothered by the secretion, sinks down on 

 the sessile glands and dies. Another difference is, 

 that the secretion from the tall glands, before they 

 have been in any way excited, is strongly acid, and 

 perhaps contains a small quantity of the proper 

 ferment. Again, these glands do not secrete more 

 copiously from being excited by the absorption of 

 nitrogenous matter ; on the contrary, they then absorb 

 their own secretion with extraordinary quickness. In 

 a short time they begin to secrete again. All these 

 circumstances are probably connected with the fact 

 that insects do not commonly adhere to the glands 

 with which they first come into contact, though this 

 does sometimes occur; and that it is chiefly the se- 

 cretion from the sessile glands which dissolves animal 

 matter out of their bodies. 



KORIDULA. 



Boridiila dentata. — This plant, a native of the western 

 parts of the Cape of Good Hope, was sent to me in a 

 dried state from Kew. It has an almost woody stem 

 and branches, and apparently grows to a height of 

 some feet. The leaves are linear, with their summits 

 much attenuated. Their upper and lower surfaces 

 are concave, with a ridge in the middle, and both are 

 covered w^ith tentacles, which differ greatly in length ; 

 some being very long, especially those on the tips 

 of the leaves, and some very short. The glands also 

 differ much in size and are somewhat elongated. 

 They are supported on multicellular pedicels. 



This plant, therefore, agrees in several respects with 



