308 DESCRIPTION OF [Poli/gastrica. 



species by coloured food. The mouth and discharging 

 orifice are both on the ventral surface, the former having 

 a protruding tongue-like member. The propagative organs 

 are delicate strings of ova, formed in a net-like manner, 

 whose exclusion has been seen in one species ; a bright 

 contractile round vesicle is observable in two species, and 

 in another species two vesicles or sexual bladders are pre- 

 sent. A large round or oval gland in the centre of the 

 body has been seen in two species. Transverse and longi- 

 tudinal self-division has been noticed by several observers, 

 and in K. cucullus a skin or envelope. 



507. KoLPODA cucullus (M.) The cap-like Kolpoda. — 

 Body turgid, slightly compressed ; its form that of a kid- 

 ney, often attenuated anteriorly. Ehrenberg states the 

 mouth is closed by a little fleshy tongue ; this is most 

 distinctly seen in Paramecium aurelia. When the ova are 

 deposited, a collapse of the body ensues, and hence a change 

 of form. When very young they are difficult to distin- 

 guish from the Monads. Plate vii., fig. 324, represents 

 the normal form of this species. Fig. 325 represents the 

 animalcule depositing its ova in a net-like mass, andjigures 

 326, 327, and 328, are three young animalcules, which 

 resemble Trichoda pyriformis. Common in vegetable 

 infusions. Size 1-1 800th to l-280th. 



508. Kolpoda (?) ren. The kidnet/shaped Kolpoda has 

 an ovato-cylindrical body, kidney-shaped, and rounded at 

 the ends. Found in river water. Size l-288th. 



509. Kolpoda (?)cMC?<//20 (M.) The elliptical Kolpoda. 

 — Body compressed, plane, elliptical, slightly sinuated an- 

 teriorly. Ehrenberg remarks neither cilii or tongue-like 

 member was observable by him : hence its generic situation 

 is uncertain. Size 1-yOOth. 



