JOURNAL OF MICROSCOPICAL SCIENCE. 



EXPLANATION OF PLATE XXIII, 



Illustrating Mr. Francis Darwin's paper on the Process of 

 Aggregation in the Tentacles of Drosera rotundifolia. 



Fig. 1. — A cell from the pedicel of the tentacle, in a normal unaggre- 

 gated condition. It is filled with a homogeneous crimson fluid through 

 ■which protoplasmic currents and yellow chlorophyll bodies are faintly 

 seen. 



Fig. 2. — A cell in the aggregated condition produced by a solution of 

 carbonate of ammonia. A large vacuole seen in one of the masses of 

 aggregated matter. 



Fig. 3. — A cell which has lately died in a state of aggregation; the 

 flowing protoplasmic network is coagulated and is seen stretching from one 

 chlorophyll body to the next. 



Pig. 4. — Part of a cell showing chlorophyll bodies collected into a heap 

 by the action of carbonate of ammonia (part of cell omitted). 



Fig. 5. — A cell in an aggregated condition ; the cover glass having been 

 pressed ; the firm consistency of the aggregated masses in the later stages 

 of aggregation is shown by the way in which they break into starlike forms. 



Fig. 6. — A cell in which aggregation was produced by an infusion of 

 raw meat, a, b, c, d, and e, show changes of form successively assumed by 

 the aggregated matter ; the changes occurred so rapidly that it was impos- 

 sible to copy the appearance of the whole cell at a given moment. 



Fig. 7. — A cell which is undergoing dissolution of the state of aggrega- 

 tion, drawn at successive periods, A being the earlier of the two. It shows 

 the change from a light to a dark colour which occurs, this change travelling 

 up the gland from cell to cell and also up each individual cell. Simple 

 changes of form are also shown. 



Fig. 8. — Shows the streaming network of protoplasm ia a pale cell con- 

 taining chlorophyll bodies. The current is seen to flow from one chlorophyll- 

 body to another. 



Fig. 



Fig. 



\' -■ Q ^ Simpler currents in pale cells. 



