Geology and Natural History. 155 
on this subject with the following paragraph: 
Among the most interesting results of the experiments was the 
observation that certain poisons which act with extreme violence 
eble i 
da 
following Tuesday. A specimen of Lunatia heros, into which a 
quantity of woorara had been injected, was found the next day to 
show no sign of any inj Indeed, both of these poisons seemed 
When | ept for a number of hours in sea water. Cyan f 
potassium is similar in its effects, though not quite so instantane- 
ously fatal. The effects of quinine are similar, though less 
meh remarked that he had supposed that Amceba swallows food 
= and below, between which the cba was examined 
: Soiree prevented the Urocentrum from escaping. e condi- 
to ot mprisonment of the latter was so peculiar that he was led 
® Watch it, 
tase, of the Ameeba, above and below, and gradually extended 
aay So as to convert the circle of the pseudopods into a 
plete sac, inclosing the Urocentrum. Another of these crea- 
