THE SCHOOL OF THE SHORE 57 
keep till we come to the fresh-water haunt. 
Less familiar is the case of a tropical shore-fish 
(the Gaff Topsail), which has only a few eggs, 
and lives in places where the struggle for 
existence is very keen. What is it to do? The 
male fish takes the eggs in 
his mouth and keeps them 
there until they are hatched. 
One would think it must be 
difficult not to swallow them, 
but he fasts all the time. 
There are many other 
examples of “love” on the 
seashore. The marine leech 
or Skate-sucker (Pontobdella 
muricata), a warty green 
animal, is both male and 
female at once, like earth- 
worms and snails. It is a ee 
very careful parent, deposit- _ vetta). 
: ; : A Marine Leech that 
ing the e268 1m COCOONS ID* tates erect care of 
side empty shells of bivalves, **s Fags. 
and mounting guard over them for many 
weeks. It is interesting to find examples of 
marked parental care on the lower rungs of 
the ladder of life. One of the humblest illus- 
trations is to be found in a British star-fish, 
