170 FUNCTIONS AND INSTINCTS. 



submitted to a stricter examination, more correct 

 ideas were substituted for these mistaken ones, 

 and the zoophytes, or polypes, were generally 

 admitted to be real animals, though some, after 

 Linne, still regard them as something between 

 animal and vegetable. Trembley was one of 

 the first who ascertained their animal nature ; 

 he saw the fresh-water polypes, by means of 

 their long tentacles, seize and swallow certain 

 grubs, and also many minute Entomostracans* 

 common in stagnant water. These polypes so 

 used their tentacles as evidently to indicate a 

 degree of volition, sometimes using one and some- 

 times many, as circumstances required. When 

 they had secured their prey, they contracted and 

 gave a curve to these organs, so as to bring it near 

 the orifice, or mouth, at their anterior extremity, 

 which then began to open, and the animal they 

 had caught was gradually absorbed. He -has 

 seen them attack small fishes, also wprms, larvae 

 and pupae of gnats, parts of slugs, entrails, and 

 even pieces of meat. 



The marine polypes are equally ravenous with 

 the river ones, feeding upon whatever they can 

 lay hold of, sometimes, like the wheel-animals, 

 or rotatories, producing a vortex in the water, 

 and thus causing a flow to their mouth of the 

 infusory, and other animalcules contained in that 



1 Monoculi. Linn. 



