602 DESCRIPTION OF \_Folygastrica. 



same nature, and I ■would say, of nearly the same consistence. 

 They have a mouth also, but no anus ; vacuolae formed at the 

 bottom of the mouth, as a result of an impulsive force, produced by 

 the vibratile cilia on the surrounding liquid, hollowed out in any 

 part ; and lastly granules, varying in kind, desseminated through 

 the mass, and which I cannot admit as determinate organs, or as 

 ova. This account varies materially from that of Ehrenberg. 



Ploesconia 'patella = Euplotes patella. — -P. vannus. — Body 

 depressed, oblong, oval; very transparent, smooth, without striae, 

 5 — 8 anterior hooks ; and 7 — 8 straight styles behind. Length 

 l-218th. In sea water. 



P. (?) senium. — Larger than the preceding, with the band of 

 vibratile cilia extending farther backwards, and the posterior styles 

 inflected and sinuous. 



P. balteata. — Body oval, rather narrower in front, diaphanous, 

 with 5 striae (ribs); the band of cilia extending 5-6ths the length of 

 the body; cirrhi few, feeble. Length l-325th. In sea water; no 

 hooks, as in P. vannus. 



P. cithara. — Body oval, with ten regularly disposed ribs, well 

 marked ; the row of cilia semicircular, extending two thirds its 

 length ; cirrhi not long, and almost confined to the posterior 

 extremity. Length l-290th to l-275th. In stagnant sea water. 



P. crassa. — Body oval, oblong ; thick, but diaphanous, with some 

 faint signs of ribs ; the band of cilia little curved, and extending one 

 half the length ; 6 — 8 curved cirrhi at anterior, and 5 — 7 straight 

 ones at posterior extremity. Length l-3G2d. Found with the pre- 

 ceding in sea water. 



P. Charon. — Body irregularly oval, truncate in front, narrower 

 behind, with well marked irregular ribs ; cirrhi long, not curved. 

 Differs much from Euplotes Charon (Ehr.) 



P. affinis differs from P. Charon, by its habitat being in fresh 

 water, and by having its anterior portion narrower, whilst its pos- 

 terior is more rounded and less plaited. 



P. (?) subrotunda. — Body oval, thick, granular within ; no distinct 

 ribs ; truncated and fissured in front, styles long and thin at each 

 end. Length l-535th to l-47oth. In infusions. 



P. (?) radiosa. Longer than the preceding, 1 -520th to l-395th. 



