54 LIFE AND HER CHILDREN. 
great reason why the hydra should take it so quietly ; 
he does not wish to waste his lassos, for a cell once 
burst cannot be used again, and he will have to 
grow a new one for each one that he exhausts. So 
he waits patiently for the spell to work, and does 
not hug his victim too close until he is half conquered, 
and then he draws him gently in. 
So the hydra lives and catches its food without 
needing to move far from the place of its birth. All 
the summer through it puts out buds (see b b, Fig. 
19) from its side, and these buds, as soon as their 
tentacles are grown, drop from their parent and settle 
in life for themselves, so that any pond may contain 
hundreds of them ; and when the winter comes, and 
before they all die, an egg appears near the base of 
the tubes of those which are then living, and these 
eggs lie till next spring, when they are hatched, and 
produce a new generation of hydras. 
This is the simplest lasso-thrower, and I think 
you will allow that his lasso is both wonderful and 
deadly, so that, though these hydras are the only 
lasso-throwers to be found in fresh water," 5 ' it is easy 
to understand that his relations in the wide ocean 
should have made good use of the new weapon with 
which life has provided them, and secured homes and 
resting-places throughout the whole world of waters, 
and under all kinds of strange shapes and forms. 
From the North Sea to the Tropics, from the 
pools on the shore at low tide to the depths of the 
wide ocean, we meet everywhere with this division of 
" lasso-throwers." Now in the shape of large jelly-fish 
* Since the above was written, a fresh-water Medusa has been found 
in the tank of the Victoria Regia in the Botanical Gardens, Regent's 
Park. 
