MANUAL OF NATURAL HISTORY. 669 



plunged into fresh-water to prevent them from throw- 

 ing off their arms, and then transferred to the spirit ; 

 to preserve them dry, they should be dipped for a 

 moment in boiling-water, dried in a current of air 

 and packed in paper. The Sea-urchins or Echinidce, 

 after the inside has been carefully removed, pre- 

 serv ing, however, the skeleton of the " lanthorn" or 

 jaws, should be sewed up separately in muslin bags, 

 to preserve their spines, previously having sub- 

 mitted them, for several hours, to a bath of fresh- 

 water. 



When parasites are found, such as Cavitary or 

 Parenchymatous Entozoa, the part to which the 

 animal is attached should be removed along with it, 

 in order to preserve the mouth, hooks, or sucking 

 disk by which it adheres. These kinds of animals 

 will be found in the intestines, liver, &c., of many 

 animals which are opened, and also adhering to the 

 gills and noses of fish. They should all be carefully 

 collected and placed in alcohol diluted with about 

 a third of fresh- water. Coloured drawings should 

 be made of Sea-nettles or Acalephce, as the beauty 

 of their forms is never preserved after death, even in 

 spirits; they must be placed in tumblers of sea- 

 water, and drawn while in their living state. After 

 placing them in the spirit it must frequently be 

 changed after the specimens have remained in it for 

 some time, as a very large amount of fluid exudes 

 from their gelatinous bodies, and weakens its preserv- 

 ative power. 



Fleshy-polyps, Sea-anemones, and similar forms 



