18 2 Of the frefh Water Polype. 
tra£t himfelf, or to draw near his prey, and in an inflant 
the entangled millipedes is conveyed to the mouth, againfl: 
which it is held and fubdued. 
When a polype hath nothing to eat, its mouth is ge¬ 
nerally open, but that fo fmall that it cannot be feen 
without the affiftance of a magnifying glafs: whereas, as 
foon as the arms have conveyed a prey to the mouth, it 
opens itfelf more, and always in proportion to the fize of 
the animal that is to be devoured; its lips gradually 
dilate, and precifely adj ull themfelves to the figure of 
their prey. 
All the worms which are feized by the polypes, do 
not prefent themfelves in the lame manner to their mouth ; 
for if the worm prefents itfelf by one of its extremities, 
it is not requifite the polype fhould open its mouth con- 
fiderably, neither does it open otherwife, but precifely to 
give entrance to the worm, fig. 366. 
If the worm is not too long for the ftomach, it remains 
therein extended; but if longer, that end which firft en¬ 
tered bends, and when it is entirely fwallowed it may be 
feen folded within the polype, fig. 379. 
When the middle or any other part of the worm is 
prefented to the polype’s mouth, it feizes this part with 
its lips, extending them on both fides, and applying them 
againft the worm 5 at which time its mouth takes the 
form of a boat pointed at each end, fig. 368. after which 
the polype gradually clofes the two points of its boat¬ 
like lips, which doubles the worm in that part, and fo 
it is fwallowed, fig, 369. 
As foon as the ftomach is filled, its capacity and the 
Ikin thereof is augmented, and the body becomes Ihort, 
fig, 372. its arms alfo are for the moft part contra&ed. 
The polype hangs down without motion, and appears 
to be in a ftate of numbnels, and in ihape very different 
from 
