46 
withim the clutches of the merciless polyp. The hydra:produces 
young’ by budding, and does not seem to object to being turned 
inside out.or cut into pieces. Should these remarks on a fresh 
water creature have seemed like a digression, it will now be seen 
that they are not really so, because the hydra.is the type of a very 
large number of marine polyps, to which the term hydroids is 
applied. They are like the hydra itself, hollow-bodied animals 
belonging to the great sub-kingdom called Celenterata, which is 
wide enough to take in such interesting creatures as the jelly fish, 
the sea anemone, and the coral building polyp. Those whitish 
branched plant-like things that are found on the beach in such 
plenty, and are so commonly called seaweeds, are zoophytes or 
colonies of hyroid avimals. Thousands of the tiny animals, polyp- 
ites as they are called, often inhabit a single polypidom, each 
animal being lodged in a hydrotheca, and all the members of the 
colony being organically united through the common flesh that 
runs down the stem. It is by budding—much as plants bud—that 
the colony is built up from a single animal, and, of course, the 
polypidom itself is formed by the united work of the animals them- 
selves. The tentacles of the hydroid animal are furnished with 
thread cells and darts, like those of the hydra itself. Sertularia 
abietina, a deep-water species (specimen), is very commonly seen 
(Hincks, vol I., 266; vol. IL., p, 55) growing on the shell of the 
common scallop. Fine specimens are as much as a foot high, and 
branched bipinnately, are very handsome. Lach little polypite has 
the mouth furnished with about 26 or 30 tentacles. 
Hydra-like animals are very numerous, and are divided into many 
genera, to only one of which— /ubularia—your attention is asked 
for a minute or two. Tubularia indivisa (specimen) grows on our 
rocks, and is most likely plentiful here and there, The colony is 
made up of a number of simple stems, often twisted and interwoven 
at the base. Hach stem has.a thread of flesh running down to the 
root, and is crowned with a deep red polypite, of the beauty of 
which words cannot give any proper idea. The writer, who has 
seen this lovely animal-plant, with the plate-like tentacles spread 
out, would fain dwell upon its charms, but time forbids. and it may 
be that we do uot all see with the same eyes. However, let the 
coloured plant tell its own tale, Professor Allman, in the work 
now before you, has described and beautifully figured the Tubularian 
Hydroids, ; 
Wonderful creatures are the well-known jelly fish or sea nettles. 
—the meduse of naturalists. In Cuvier’s Animal Kingdom they are . 
called Acalephe, on account of the stinging and smarting that is 
caused by contact with them. Certainly they are not quite bad 
enough in thei tastes and dispositions to be fairly named after 
