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Pa; AT E XVII 
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VORTICELLA URCEOLARIS. 
GENERIC CHARACTER. 
A fmall animal, with a vafcilar cup; the mouth is at one end, 
ciliated, and capable of being contracted ; the ftem fixed. 
SPECIFIC CHARACTER. 
Single, with a fhort tail, and toothed mouth. 
This Animalcum is barely perceptible to the naked eye, appearing — 
like a {mall white fpeck ; the microfcope difcovers the external co- 
vering to be fo tranfparent, that all the motions of the animal within 
are perfectly diftinét. It has a double rotatory inftrument, which, 
however, it can conceal or fhew at pleafure ; and it has power to 
protrude the head and tail as at Fic. 1. or to contrac them within — 
the external coat or covering, as at Fic. 2.—When the animal 
intends to difplay its rotatory inflrument, it forces its tail through 
the hole at the extremity of the outer coat, and affixes it to whatever 
fubftance is near; but when it fwims, it moves its tail payee 
and forwards to affift it. 
This fpecies is found in river, and fagnant water. 
\ 
Bees : S FIG 
