POLYPES. 
69 
eight tentacula ; others florid, and with twenty. They 
are frequently disgorged along with the half-digested food, 
thirty-eight appearing thus at a single litter. An em- 
bryo extracted artificially from the amputated tip of a 
tentaculum began to breed in fourteen months, and sur- 
vived nearly five years. Monstrosities by excess are not 
uncommon among the young, one produced naturally 
consisting of two perfect bodies ; and their parts, sustained 
by a single base, exhibited embryos in the tentacula at 
ten months, bred in twelve, and lived above five years. 
While one body was gorged with food, the other con- 
tinued ravenous.” * 
It is interesting to see the Actinice fed ; and as they are 
very voracious, they are rarely unwilling to gratify their 
benefactors with a display of their swallowing powers. 
Their natural prey consists of the smaller Mollusca, Anne- 
lida, Star-fishes, Crustacea, and, in short, of any animals 
which they are able to seize and to retain. The tentacles 
have the same prehensile power as those of the Hydra, — a 
power which depends on the presence of projectile barbed 
weapons, ordinarly coiled in elastic cells. These organs 
are found in inconceivable multitudes imbedded in the 
tissues of the tentacles, of the lips, of the stomach, of the 
frilled ovarian bands, and especially, in some species, in 
long threads which are protruded from pores in the integu- 
ment of the body. 
The structure of these weapons is as follows : — Each con- 
sists of an oval or elliptical sac of transparent membrane, 
within which is seen a thread coiled up, and in some 
instances an oblong or lozenge-shaped chamber. At the 
* Kep. Br. Assoc. 1834 ; and Edin. New Phil. Joum. xvii. 
