208 DROSERA ROTTJNDIFOLIA. CHAP. IX 



expanded. The tentacles were now examined, and the aggregated 

 masses were almost wholly redissolved ; the cells being filled with 

 <4iomogeneous purple fluid, with the exception here and there of 

 a single globular mass. We thus see how completely the proto- 

 plasm had escaped all injury from the poison. As the glands 

 were soon rendered quite white, it occurred to me that their 

 texture might have been modified in such a manner as to 

 prevent the poison passing into the cells beneath, and conse- 

 quently that the protoplasm within these cells had not been at 

 all affected. Accordingly I placed another leaf, which had been 

 immersed for 48 hrs. in the poison and afterwards for 24 hrs. in 

 water, in a little solution of one part of carbonate of ammonia 

 to 218 of water ; in 30 m. the protoplasm in the cells beneath 

 the glands became darker, and in the course of 24 hrs. the 

 tentacles were filled down to their bases with dark-coloured 

 spherical masses. Hence the glands had not lost their 

 power of absorption, as far as the carbonate of ammonia is 

 concerned. 



From these facts it is manifest that the poison of the cobra, 

 though so deadly to animals, is not at all poisonous to Drosera ; 

 yet it causes strong and rapid inflection of the tentacles, and 

 soon discharges all colour from the glands. It seems even to act 

 as a stimulant to the protoplasm, for after considerable expe- 

 rience in observing the movements of this substance in Drosera, 

 I have never seen it on any other occasion in so active a state. I 

 was therefore anxious to learn how this poison affected animal 

 protoplasm ; and Dr. Fayrer was so kind as to make some obser- 

 vations for me, which he has since published.* Ciliated epi- 

 thelium from the mouth of a frog was placed in a solution of 

 03 gramme to 4 - 6 cubic cm. of water ; others being placed 

 at the same time in pure water for comparison. The move- 

 ments of the cilia in the solution seemed at first increased, 

 but soon languished, and after between 15 and 20 minutes 

 ceased ; whilst those in the water were still acting vigorously. 

 The white corpuscles of the blood of a frog, and the cilia on two 

 infusorial animals, a Paramsecium and Volvox, were similarly 

 affected by the poison. Dr. Fayrer also found that the muscle 

 of a frog lost its irritability after an immersion of 20 m. in 

 the solution, not then responding to a strong electrical current. 

 On the other hand, the movements of the cilia on the mantle of 

 an Unio were not always arrested, even when left for a consider- 



' Proceeding's of Royal Society ' Feb. 18, 1875. 



