200 DROSERA ROTUNDIFOLIA. Chap. IX. 



were excited, after an interval of a quarter to three quarters of 

 an hour, by being rubbed or given bits of meat. Similar drops 

 of a solution of one part to 218 of water (2 grs. to 1 oz.) quickly- 

 blackened the glands ; some few tentacles thus treated moved, 

 whilst others did not. The latter, however, on being subse- 

 quently moistened with saliva or given bits of meat, became 

 incurved, though with extrepie slowness; and this shows that 

 they had been injured. Stronger solutions (but the strength 

 was not ascertained) sometimes arrested all power of movement 

 very quickly ; thus bits of meat were placed on the glands of 

 several exterior tentacles, and as soon as they began to move, 

 minute drops of the strong solution were added. They con- 

 tinued for a short time to go on bending, and then suddenly 

 stood still; other tentacles on the same leaves, with meat 

 on their glands, but not wetted with the strychnine, continued 

 to bend and soon reached the centre of the leaf. 



Citrate of Strychnine. — Half-minims of a solution of one 23art 

 to 437 of water were placed on the discs of six leaves ; after 

 24 hrs. the outer tentacles showed only a trace of inflection. 

 Bits of meat were then placed on three of these leaves, but in 

 24 hrs. only slight and irregular inflection occurred, proving 

 that the leaves had been greatly injured. Two of the leaves to 

 which meat had not been given had their discal glands dry and 

 much injured. Minute drops of a strong solution of one part to 

 109 of water (4 grs. to 1 oz.) were added to the secretion round 

 several glands, but did not produce nearly so plain an effect as 

 the drops of a much weaker solution of the acetate. Particles of 

 the dry citrate were placed on six glands ; two of these moved 

 some way towards the centre, and then stood still, being no 

 doubt killed ; three others curved much farther inwards, and 

 were then fixed; one alone reached the centre. Five leaves 

 were immersed, each in thirty minims of a solution of one part 

 to 437 of water; so that each received -^ of & grain; after 

 about 1 hr. some of the outer tentacles became inflected, and 

 the glands were oddly mottled with black and white. These 

 glands, in from 4 hrs. to 5 hi's., became whitish and opaque, 

 and the protoplasm in the cells of the tentacles was well aggre- 

 gated. By this time two of the leaves were greatly inflected, 

 but the three others not much more inflected than they were 

 before. Nevertheless two fresh leaves, after an immersion re- 

 spectively for 2 hi's. and 4 hrs. in the solution, were not killed ; 

 for on being left for 1 hr. 30 m. in a solution of one part of 

 carbonate of ammonia to 218 of water, their tentacles became 

 more inflected, and there was much aggregation. The glands 



