232 DIONiEA MUSCIPULA. [Chap. XIII. 



CHAPTER Xin. 



DIONi{:A MUSCTPULA. 



Structure of the leaves Sensitiveness of the filaments Rapid movement 

 of the lobes caused by irritation of the filameutB Glands, their power 

 of secretion Slow movement caused by the absorption of animal 

 matter Evidence of absorption from the aggregated condition of the 

 glands Digestive power of the secretion Action of chloroform, 

 ether, and hydrocyanic acid The manner in which insects are cap- 

 tured Use of the marginal spikes Kinds of insects captured ^Tho 

 transmission of the motor impulse and mechanism of the movements 

 Ke-czpansion of the lobes. 



This plant, commonly called Venus' fly-trap, from the 

 rapidity and force of its movements, is one of the most won- 

 derful in the world.' It is a member of the small family of 

 the Droseraceffi, and is found only in the eastern part of 

 North Carolina, growing in damp situations. The roots are 

 small; those of a moderately fine plant which I examined 

 consisted of two branches about 1 inch in length, springing 

 from a bulbous enlargement. They probably serve, as in the 

 case of Drosera, solely for the absorption of water ; for a gar- 

 dener, who has been very successful in the cultivation of this 

 plant, grows it like an epiphytic orchid, in well-drained damp 

 moss without any soil.* The form of the bilobcd leaf, with its 

 foliaceous footstalk, is shown in the accompanying drawing 

 (Fig. 12). The two lobes stand at rather less than a right 

 angle to each other. Three minute pointed processes or fila- 

 ments, placed triangularly, project from the upper surfaces 

 of both; but I have seen two leaves with four filaments on 

 each side, and another with only two. These filaments are 

 remarkable from their extreme sensitiveness to a touch, as 

 shown not by their own movement, but by that of the lobes. 



* Dr. Hooker, In hlft addroBii to pnrt to ropont them. [A good ac- 



the British Assoclntlon at Bel- count of the onrly Ilt)>riitiire is 



fast, 1874, has given ho full an given l>y Kiirts in Relchert and 



blntorionl account of the obsorvn- l)u Bols-Reymond's * Archlv.' 



tlons which have been publlshi^d 1876. F. I>. ) 



on the habits of this plant, that ' ' Gardener's Chronicle,' 1874, 



it would l>e superfluous on my p. 464. 



