64 PLATE XXIX. 



^ FIG. III. . 



VORTICELLA VIRIDIS. 



GEJSfERIC CHARACTER. 



A worm capable of contra^ing or extending itfelf, naked, with 

 rotatory cilia, 



SPECIFIC CHARACTER. 

 .Cylindrical uniform, green, and opake. MuIIer's Anlm. Infuf, 



The naked eye difcovers this fpecies as a mere point : when magni- 

 fied it is of a dark green colour, almoft opake, nearly cylindrical, 

 obtufe at the extremities, and deftilute of limbs. It moves circularly, 

 or in a ftrait direction, and caufes fuch an agitation of the water, that 

 notwithftanding its appearance, fome rotatory inftrument muft be con- 

 cealed within the body, which the infect can put forth at pleafure. 



PLATE 



