Omar, XV. ABSORPTION. 337 
have been slightly acted on and rendered soluble 
within the above stated short periods. 
The glands have not only the power of rapid absorp- 
tion, but likewise of secreting again quickly ; and this 
latter habit has perhaps been gained, inasmuch as 
insects, if they touch the glands, generally withdraw the 
drops of secretion, which have to be restored. The exact 
period of re-secretion was recorded in only a few cases. 
The glands on which bits of meat were placed, and which 
were nearly dry after about 1 hr. 30 m., when looked 
at after 22 additional hours, were found secreting; so 
it was after 24 hrs. with one gland on which a bit 
of albumen had been placed. The three glands to 
which a minute drop of a solution of nitrate of 
ammonia was distributed, and which became dry after 
2 hrs., were beginning to re-secrete after only 12 addi- 
tional hours. 
Tentacles Incapable of Movement.—Many of the tall 
tentacles, with insects adhering to them, were care- 
fully observed ; and fragments of insects, bits of raw 
meat, albumen, &c., drops of a solution of two salts 
of ammonia and of saliva, were placed on the glands 
of many tentacles; but not a trace of movement could 
ever be detected. I also repeatedly irritated the 
glands with a needle, and scratched and pricked the 
blades, but neither the blade nor the tentacles became 
at all inflected. We may therefore conclude that 
they are incapable of movement. 
On.the Power of Absorption possessed by the Glands.— 
It has already been indirectly shown that the glands 
on pedicels absorb animal matter; and this is further 
shown by their changed colour, and by the aggregation 
of their contents, after they have been left in contact 
with nitrogenous substances or liquids. The following 
observations apply both to the glands supported on 
