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Microscopical Essays-. 



the water, and keep it fo for a minute ; after which, thru ft the 

 point of the pencil, together with the anterior end, by little and 

 little under water, until no more than about half the tenth of an 

 inch of the polype's tail remains above it's furface ; at this inftanr, 

 with the pointed quill remove that part of the polype from the 

 pencil which is already in the water, and at the fame time blow- 

 ing againft the polype, it will be loofened, and remain out of 

 the water. 



When the polypes were flrft difcovered, Mr. Trembley had 

 fome difficulty to find out that food which was proper for them 

 but he fqon difcovered, that a fmall fpecies of the millepede 

 anfwered the purpofe very well : the pulices aquatices have alfo 

 been recommended. The fmall red worms", which are to be 

 found on the mud-banks of the Thames, particularly near the 

 fhores, anfwer the purpofe alfo ; they are eaiily found when the 

 tide is out, when they rife in fuch fwarms on the furface of the 

 mud, that it appears of a red colour. Thefe worms are an ex- 

 cellent food for the polype. If a fufficient quantity is gathered in 

 November, and put into a large glafs full of water, with three ot 

 four inches of earth at the bottom, you will have a fupply for the 

 polypes all the winter. They may alfo be fed with common 

 worms, with the larva of gnats and other infects, and even with 

 butchers meat, &c. if it be cut fmall enough. 



River, or any foft water, agrees with them ; hut that which is. 

 hard and (harp prevents their thriving, and generally kills them 

 in a few days. The worms with which they are fed mould be 

 always 'cleanfed before you ieed the polypes with them. 



