POISONS, 995 
irritability had supervened, recovery began in ten 
minutes after re-immersion, and was complete in 
half an hour. 
In Tiaropsis the symptoms of nicotin poisoning 
are also well marked. When gradually adminis- 
tered, the first effect of the narcotic is a complete 
loss of co-ordination in the swimming motions. A 
slight increase of the dose brings about a tonic 
spasm, which differs from the natural spasm of 
these animals—(a) in being stronger, so that the 
nectocalyx becomes bell-shaped rather than square, 
(6) in being much more persistent, and (c) in under- 
going variations in its intensity from time to time, 
instead of being a contraction of uniform strength ; 
thus the spasm temporarily affects some parts of 
the nectocalyx more powerfully than other parts, 
so that the organ may assume all sorts of shapes. 
Such distortions proceed even further under the 
influence of nicotin than under that of strychnine, 
etc. Sometimes, for instance, one quadrant will 
project in the form of a pointed promontory; at 
other times two adjacent or opposite quadrants 
will thus project, and occasionally all four will do 
so, the animal thus becoming star-shaped. Some- 
times, again, one quadrant will be less contracted 
than the other three, while at other times more or 
less slight relaxations affect numerous parts of the 
bell, its margin being thus rendered sinuous, though 
more or less violently contracted in all its parts. 
This state of violent spasm lasts for several minutes, 
when it gradually passes off, the nectocalyx relaxing 
into the form of a deep bowl and remaining quite 
