96 DROSERA ROTUNDIFOLIA. (Crap. VI. 
A few trials were made with cheese; cubes of iy of an 
‘inch (1:27 mm.) were placed on four leaves, and these after 
one or two days became well inflected, their glands pouring 
forth much acid secretion. After five days they began to re- 
expand, but one died, and some of the glands on the other 
leaves were injured. Judging by the eye, the softened and 
subsided masses of cheese, left on the discs, were very little 
or not at all reduced in bulk. We may, however, infer from 
the time during which the tentacles remained inflected,— 
from the changed colour of some of the glands,—and from 
the injury done to others, that matter had been absorbed from 
the cheese. 
Legumin.—I did not procure this substance in a separate 
state; but there can hardly be a doubt that it would be easily 
digested, judging from the powerful effect produced by drops 
of a decoction of green peas, as described in the last chapter. 
Thin slices of a dried pea, after being soaked in water, were 
placed on two leaves; these became somewhat inflected in 
the course of a single hour, and most strongly so in 21 hrs. 
‘They re-expanded after three or four days. The slices were 
not liquefied, for the walls of the cells, composed of cellulose, 
are not in the least acted on by the secretion. 
Pollen.—A little fresh pollen from the common pea was 
placed on the discs of five leaves, which soon became closely 
inflected, and remained so for two or three days. 
The grains being then removed, and examined under the 
microscope, were found discoloured, with the oil-globules 
remarkably aggregated. Many had their contents much 
shrunk, and some were almost empty. In only a few cases 
were the pollen-tubes emitted. There could be no doubt 
that the secretion had penetrated the outer coats of the 
grains, and had partially digested their contents. So it 
must be with the gastric juice of the insects which feed on 
pollen, without masticating it.* Drosera in a state of nature 
cannot fail to profit to a certain extent by this power of 
digesting pollen, as innumerable grains from the carices, 
grasses, rumices, fir-trees, and other wind-fertilised plants, 
which commonly grow in the same neighbourhood, will be 
* Mr. A. W. Bennett found the tera; see ‘Journal of Hort. Soc. of 
‘undigested coats of the grains in the — London,’ vol. iv. 1874, p. 158. 
intestinal canal of pollen-eating Dip- 
