Of the frejh Water Polype . 18 1 
The polypes we breed and feed, are commonly in- 
fefied with little lice, it is therefore neceflary to cleanfe 
them from thefe tormentors, by rubbing them with an 
hair pencil, and if the polypes fufpend themfelves from 
the furface of the water, it is fcarce pofiible for them to 
be freed from thefe lice. In that cafe make the polypes 
fix themfelves to a packthread, or fix them to it, as at 
fig. 367. at the place b, letting the two ends h f, and 
k g hang down over the edges of the glafs. One may 
then flroke them even fomething rudely, backwards and 
forwards, with an hair pencil, without pulling them off, 
and in changing the water, only take hold of each end 
of the pack-thread, draw it gently out of the water, and 
put it immediately into another glafs, prepared for its re¬ 
ception. If feveral of thefe pack-thread firings are put 
into a glafs well flored with polypes, there will be always 
fome that will fix n themfelves thereto. 
When the arms of the polype are well extended, put a 
millipedes, or any other worm into the glafs, and with 
the point of a pencil, pufli it to one of the arms, which 
it no fooner touches, but it is feized, and when the mil¬ 
lipedes m, c, n, or worm, perceives itfelf taken, it en¬ 
deavours by very quick and ftrong efforts to difengage 
itfelf, often fwimming and dragging the arm a c, fig. 
367. from one fide of the glafs to the other; this violent 
motion of the millipedes, obliges the polype to contract 
its arms, in the performance of which he often difpofes 
them in the form of a corkfcrew, o i, which alfo con¬ 
tributes to the fhortening of it. The millipedes by its 
continual ftruggles, entangles itfelf in the arm that holds 
it, m i n, and often meeting with other arms, they alfo 
aififl, and with a fudden pull, enable the polype to con- 
N 3 tradl 
* Hifl. de Polyp, p. 85. 
