194 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
after entrance, aggregated 36 percent of all individuals in the sin- 
istral series, 20 percent for the “indifferent” and 16 percent in the 
normal series. The observed cases where glaucothoe abandoned 
their shells when disturbed, were 7 percent in the sinistral experi¬ 
ments, but only 1 percent in the normal. In the “ indifferent ” 
experiments no specimen was observed to act in this manner. More¬ 
over, a single dextral shell dropped into an aquarium will certainly 
be found and used. 
When several glaucothoe are placed in a dish on the bottom of 
which there are scattered various shells, we find that as each larva 
stops swimming, settles down and crawls on the bottom, it examines 
the objects in its path and is apt to enter the first that has a cavity 
in it. Then, if not satisfied, it either recommences swimming or, 
more usually, makes a further search dragging about its newly 
acquired house. It is well known (Agassiz, ’75 ) that in the inves¬ 
tigation and use of a shell the glaucothoe handle the shell exactly 
in the same manner as do adults. My observations would make 
them subject also to the same limitations. 
Like other investigators, I have not been able to repeat the obser¬ 
vation (Brooks, ’99) that hermit crabs “ even make vacant [a shell] 
that seems eligible by pulling out its occupant piece by piece and 
eating him,” although a dead snail is quickly devoured by the crabs 
and the emptied shell not infrequently used. If the snail, while the 
crabs are pulling and picking at it, gets pulled out bodily, the vacant 
shell may indeed be taken by one of the diners, but more usually the 
crabs devote their attention to the meat and leave the shell unno¬ 
ticed. I have never seen anything which would imply an inten¬ 
tional or necessary connection between the eating of the snail and 
the use of the vacant shell. When, however, a crab is searching for 
a shell he acts in a very different manner, attempting to pull out the 
dead meat bodily, just as other rubbish is removed from a shell 
that is being examined. The snail may be eaten after removal, and 
I have seen a shell-hunting crab eat fragments which were torn off 
while he was trying to extract the snail. But this is unusual; for, 
as a rule, if the snail does not come out readily the crab either aban¬ 
dons the attempt, or if desperately in need of a residence crowds in 
between the meat and the shell. 
