It is convenient for many experiments to suspend a polype from the surface of the water. To effect this, take a hair pencil in one hand, and hold a pointed quill in the other; with the pencil loosen the polype from the receiver in which it is kept, and gradually raise it near the top of the water, so that the anterior end may be next the point of the pencil; then lift it out of the water, and keep it so for a minute; after which, thrust the point of the pencil, together with the anterior end, by little and little under water, until no more than about the twentieth part of an inch of the polype’s tail remains above its surface; at this instant, with the pointed quill remove that part of the polype from the pencil which is already in the water, at the same time blowing against the polype, by which it will be loosened, and remain out of the water. When the polypes were first discovered, Mr. Trembley had some difficulty to find out the food which was proper for them; but he soon discovered, that a small species of the millepede answered the purpose very well: the pulices aquatices have also been recommended. The small red worms, which are to be found on the mud-banks of the Thames, particularly near the shores, answer the purpose also, they are easily found when the tide is out, when they rise in such swarms on the surface of the mud, that it appears of a red colour. These worms are an excellent food for the polype. If a sufficient quantity be gathered in November, and put into a large glass full of water, with three or four inches of earth at the bottom, you will have a supply for the polypes all the winter. They may also be fed with common worms, with the larva of gnats and other insects, and even with butcher’s meat, &c. if it be cut small enough. River, or any soft water, agrees with them; but that which is hard and sharp prevents their thriving, and generally kills them in a few days. The worms with which they are fed should be always cleansed before you feed the polypes with them. The polypes are commonly infested with little lice; from these it is necessary to free them, in order to preserve your polypes in a good state of health. They may be cleansed from the lice by rubbing them with a hair pencil; this cannot be easily done, unless they adhere to some substance: so that if they are suspended from the surface of the water, you must endeavour to get them to fix themselves to a piece of packthread; when they are fastened thereto, you may then rub them with a hair pencil, without loosening them from the thread. The lice which torment the polype are not only very numerous, but they are also very large proportionably to its size: they may be said to be nearly as large with respect to them, as a common beetle is to us. If not rubbed off, they soon cover their bodies, and in a little time totally destroy them.