Chap. I.] 



ACTION OP THE PARTS. 



9 



terior tentacles increasing in length in due proportion, as they 

 stand nearer to the circumference. 



The kind of inflection which the tentacles undergo is best 

 shown when the gland of one of the long exterior tentacles is 

 in any way excited; for the surrounding ones remain un- 



FlG. 4. 

 {Drosera rotundifolia.) 

 Leaf (enlarged) with all the tenta- 

 cles closely inflected, from immer- 

 sion in a solution of phosphate of 

 ammonia (one part to 87,500 of 

 water). 



Fig. 5. 

 (Drosera rotundifolia.) 

 Leaf (enlarged) with the tentacles 

 on one side inflected over a bit 

 of meat placed on the disc. 



affected. In the accompanying outline (Fig. 6) we see one 

 tentacle, on which a particle of meat had been placed, thus 

 bent towards the centre of the leaf, with two others retaining 

 their original position. A gland may be excited by being 

 simply touched three or four times, or by prolonged contact 

 with organic or inorganic objects, and various fluids. I have 

 distinctly seen, through a lens, a tentacle beginning to bend 

 in ten seconds, after an object had been placed on its gland; 

 and I have often seen strongly pronounced inflection in under 

 one minute. It is surprising how minute a particle of any 

 substance, such as a bit of thread or hair or splinter of glass, 

 if placed in actual contact with the surface of a gland, suf- 

 fices to cause the tentacle to bend. If the object, which has 



