374 PINGUICULA VULGAEIS. Chap. XVI. 



Experiment 9. — A chain of fibres of roast meat, as thin as 

 bristles and moistened with saliva, were placed down one whole 

 side, close to the narrow, naturally incurved edge of a leaf. 

 In 3 hrs. this side was greatly incurved along its whole length, 

 and after 8 hrs. formed a cylinder, about -^ of an inch (1-27 

 mm.) in diameter, quite conceahng the meat. This cylinder 

 remained closed for 32 hrs., but after 48 hrs. was half unfolded, 

 and in 72 hrs. was as open as the opposite margin where no 

 meat had been placed. As the thin fibres of meat were com- 

 pletely overlapped by the margin, they were not pushed at all 

 inwards, across the blade. 



Exferiment 10. — Six cabbage seeds, soaked for a night in 

 water, were placed in a row close to the narrow incurved edge of 

 a leaf. We shall hereafter see that these seeds yield soluble 

 matter to the glands. In 2 hrs. 25 m. the margin was decidedly 

 inflected ; in 4 hrs. it extended over the seeds for about half 

 their breadth, and in 7 hrs. over three-fourths of their breadth, 

 forming a cylinder not quite closed along the inner side, and 

 about "7 of an inch (1*778 mm.) in diameter. After 24 hrs. 

 the inflection had not increased, perhaps had decreased. The 

 glands which had been brought into contact with the upper 

 surfaces of the seeds were now secreting freely. In 36 hrs. 

 from the time when the seeds were put on the leaf the margin 

 had greatly, and after 48 hrs. had completely, re-expanded. 

 As the seeds were no longer held by the inflected margin, and 

 as the secretion was beginning to fail, they rolled soijie way 

 down the marginal channel. 



E.rperime7it 11. — Fragments of glass were placed on the 

 margins of two fine young leaves. After 2 hrs. 30 m. the 

 margin of one certainly became slightly incurved; but the 

 inflection never increased, and disappeared in 16 hrs. 30 m. 

 from the time when the fragments were first applied. With the 

 second leaf there was a trace of incurvation in 2 hrs. 15 m., 

 which became decided in 4 hrs. 30 m., and still more strongly 

 pronounced in 7 hrs., but after 19 hrs. 30 m. had plainly 

 decreased. The fragments excited at most a slight and doubtful 

 increase of the secretion; and in two other trials, no increase 

 could be perceived. Bits of coal-cinders, placed on a leaf, pro- 

 duced no effect, either owing to their lightness or to the leaf 

 being torpid. 



Experiment 12. — We will now turn to fluids. A row of drops 

 of a strong infusion of raw meat were placed along the margins 

 of two leaves; squares of sponge soaked in the same infusion 

 being placed on the opposite margins. My object was to ascer- 



