Primitive Lasso-Throwers. 39 
a portion of the stomach, until it becomes constricted and 
drops off, the tentacles meanwhile budding out from the 
distal end, and a mouth-opening arising between them. In 
the Hydra, the Actinia, and other polyps, and in truth in all 
the lower animals, budding is simply due to an increase in 
the growth and multiplication of cells at a special place on 
the outside of the body. As in the vertebrates, man included, 
the Hydra arises from an egg which, after fertilization, passes 
tnrough two stages, the germ consisting at first of two cell- 
layers, but the sexes are not separate as in the marine Hy- 
droids, which grow in colonies that may be either male or 
female. 
Like some other animals of simple structure, the Hydra 
is capable of reproducing to a most wonderful degree when 
cut into pieces. Divided in two, each becomes a perfect 
Hydra, and even when sliced into any number of thin rings 
each ring will grow out a crown of tentacles. You may 
split them into Jongitudinal strips and each strip will event- 
ually become a well-shaped Hydra. Two individuals may 
be fastened together by a horse-hair and in a short time they 
will have become like Siamese twins, but there will never 
arise the slightest disagreement between them. A Hydra 
turned inside out will readily adapt itself to the change, and 
in a few days will be able to swallow and digest bits of meat, 
its former stomach-lining having now taken upon itself the 
condition of skin. 
Hydra fusca is our simplest lasso-thrower, and the only 
one to be found in fresh waters in this country. Such a 
wonderful and deadly weapon is his, that it is easy to 
understand how his numerous relatives in the wide ocean 
have made good use of the weapon with which nature has 
provided them, and secured, under all kinds of shapes and 
forms, homes and resting-places throughout the vast waste 
of waters. From the Arctic to the Tropics, and from the 
shallow seaside pools at low tide to the fathomless abysses 
of the ocean, we meet the lasso-throwers. Now in the form 
