Ouar. 1. ACTION OF THE PARTS. 15 
tentacles remain closely inflected, the glands continue 
to secrete, and the secretion is acid; so that, if neu- 
tralised by carbonate of soda, it again becomes acid 
after a few hours. I have observed the same leaf with 
the tentacles closely inflected over rather indigestible 
substances, such as chemically prepared casein, pour- 
ing forth acid secretion for eight successive days, and 
over bits of bone for ten successive days. 
The secretion seems to possess, like the gastric juice 
of the higher animals, some antiseptic power. During 
very warm weather I placed close together two equal- 
sized bits of raw meat, one on a leaf of the Drosera, 
and the other surrounded by wet moss. They were 
thus left for 48 hrs., and then examined. The bit on 
the moss swarmed with infusoria, and was so much 
decayed that the transverse striae on the muscular 
fibres could no longer be clearly distinguished ; 
whilst the bit on the leaf, which was bathed by the 
secretion, was free from infusoria, and its striz were 
perfectly distinct in the central and undissolved por- 
tion. In like manner small cubes: of albumen and 
cheese placed on wet moss became threaded with 
filaments of mould, and had their surfaces_ slightly 
discoloured and disintegrated; whilst those on the 
leaves of Drosera remained clean, the albumen being 
changed into transparent fluid. 
As soon as tentacles, which have remained closely 
inflected during several days over an object, begin to 
re-expand, their glands secrete less freely, or cease 
to secrete, and are left dry. In this state they are 
covered with a film of whitish, semi-fibrous matter, 
which was held in solution by the secretion. The 
drying of the glands during the act of re-expan 
sion is of some little service to the plant; for I have 
often observed that objecis adhering to the leaves 
