1876.] 
New Phase of Plant-Life. 
3 
for beauty or utility to man. Its leaves are covered with" 
so-called tentacles, — hair-like filaments, generally standing 
upwards, and each carrying on its summit a gland which 
may be roughly compared to the head of a pin. These 
glands are “ each surrounded by large drops of extremely 
viscid secretion, which, glittering in the sun, have given rise 
to the plant’s poetical name of the sun-dew.” This secre- 
tion, adding to some extent like bird-lime, is the primary 
agent in capturing inserts. “ When an insedt alights on 
the central disc it is instantly entangled by the viscid secre- 
tion, and the surrounding tentacles after a time begin to 
bend, and ultimately clasp it on all sides. Insedds are 
generally killed, according to Dr. Nitschke, in about a 
quarter of an hour, owing to their tracheae being closed by 
the secretion. If an insedd adheres to only a few of the 
glands of the exterior tentacles, these soon become infledded, 
and carry their prey to the tentacles next succeeding them 
inwards ; these then bend inwards, and so onwards until the 
inse(d is ultimately carried, by a curious sort of rolling 
movement, to the centre of the leaf. Then, after an interval, 
the tentacles on all sides become infledded, and bathe their 
prey with their secretion in the same manner as if the 
insedd had first alighted on the central disc. It is surprising 
how minute an insedd suffices to cause this acdion : for 
instance, I have seen one of the smallest species of gnats 
(Culex) which had just settled with its excessively delicate 
feet on the glands of the outermost tentacles, and these 
were already beginning to curve inwards, although not a 
single gland had as yet touched the body of the insedd.” 
To measure, as it were, the sensitiveness of the glands, 
and ascertain what were the smallest bodies capable of 
inducing motion in the tentacles, a number of delicate expe- 
riments were instituted. It was found that little bits of 
human hair, measuring only 8-ioooths of an inch in length 
and weighing only 1-78740^ of a grain, caused the tentacles 
to curve inwards. The author remarks that a bit of hair 
x-50th of an inch in length, and therefore much larger than 
those used in the above experiments, was not perceived 
when placed on his tongue. “ It is extremely doubtful,” he 
adds, “ whether any nerve in the human body, even if in an 
inflamed condition, would be in any way affedded by such a 
particle supported in a dense fluid, and slowly brought in 
contact with the nerve. Yet the cells of the glands of 
Drosera are thus excited to transmit a motor impulse to a 
distant point, inducing movement. It appears to me that 
hardly any more remarkable fadd than this has been observed 
