236 DION-ffiA MUSCIPULA. [Cdap. XIII. 



almost instantly aggregated into purplish or colourless, ir- 

 regularly shaped masses of matter. The process of aggrega- 

 tion gradually travelled up the filaments from cell to cell to 

 their extremities, that is in a reverse course to what occurs 

 in the tentacles of Drosera when their glands have been ex- 

 cited. Several other filaments were cut off close to their 

 bases, and left for 1 hr. 30 m. in a weak solution of one part 

 of the carbonate to 218 of water, and this caused aggregation 

 in all the cells, commencing as before at the bases of the 

 filaments. 



Long immersion of the filaments in distilled water like- 

 wise causes aggregation. Nor is it rare to find the contents 

 of a few of the terminal cells in a spontaneously aggr^ated 

 condition. The aggregated masses undergo incessant slow 

 changes of form, uniting and again separating; and some of 

 them apparently revolve round their own axes. A current 

 of colourless granular protoplasm could also be seen travel- 

 ling round the walls of the cells. This current ceases to be 

 visible as soon as the contents are well aggregated; but it 

 probably still continues, though no longer visible, owing to 

 all the granules in the flowing layer having become united 

 with the central masses. In all these respects the filaments 

 of Dioncea behave exactly like the tentacles of Drosera. 



Notwithstanding this similarity there is one remarkable 

 difference. The tentacles of Drosera, after their glands have 

 been repeatedly touched, or a particle of any kind has been 

 placed on them, become inflected and strongly aggregated. 

 No such effect is produced by touching the filaments of 

 Dionffia; I compared, after an hour or two, some which had 

 been touched and some which had not, and others after 

 twenty-five hours, and there was no difference in the con- 

 tents of the cells. The leaves were kept open all the time by 

 clips; so that the filaments were not pressed against the 

 opposite lobe. 



Drops of water,* or a thin broken stream, falling from a 

 height on the filaments, did not cause the blades to close; 

 though these filaments were afterwards proved to be highly 



[C. De Candolle (' Archlre* Ipiifcth do not stlmulntp the leaf, 



de 8c. I'hys. et Nat.* Geneva. but that It may bo mndo to cloae 



April. 187rt HtatoB that drops of by a current of water directed at 



water which Infringe on the flla- right angles to the filament. F. 



meota In the direction of their D.] 



