16 DROSERA ROTUNDIFOLIA. Chap. 1. 



could then be blown away by a breath of air; the 

 leaves being" thus left unencumbered and free for future 

 action. Nevertheless, it often happens that all the 

 glands do not become completely dry ; and in this 

 case delicate objects, such as fragile insects, are some- 

 times torn by the re-expansion of the tentacles into 

 fragments, which remain scattered all over the leaf. 

 After the re-expansion is complete, the glands quickly 

 begin to re-secrete, and as soon as full-sized drops 

 are formed, the tentacles are ready to clasp a new 

 object. 



When an insect alights on the central disc, it is 

 instantly entangled by the viscid secretion, and the 

 surrounding tentacles after a time begin to bend, and 

 ultimately clasp it on all sides. Insects are generally 

 killed, according to Dr. Nitschke, in about a quarter 

 of an hour, owing to their tracheae being closed by 

 the secretion. If an insect adheres to only a few of 

 the glands of the exterior tentacles, these soon 

 become inflected and carry their prey to the tentacles 

 next succeeding them inwards; these then bend in- 

 wards, and so onwards, until the insect is ultimately 

 carried by a curious sort of rolling movement to the 

 centre of the leaf. Then, after an interval, the ten- 

 tacles on all sides become inflected and bathe their 

 prey with their secretion, in the same manner as 

 if the insect had first alighted on the central disc. It 

 is surprising how minute an insect suffices to cause 

 this action : for instance, I have seen one of the 

 smallest species of gnats (Culex), which had just 

 settled with its excessively delicate feet on the 

 glands of the outermost tentacles, and these were 

 ah-eady beginning to curve inwards, though not a 

 single gland had as yet touched the body of the 

 insect. Had I not interfered, this minute gnat would 



