Netv Peritrichous Infusoria, dte. By Dr. A. C. Stokes. 479 



broad, curved, transversely placed in the anterior body-half. Length 

 of body 1/225 in. ; colony often measuring 1/15 in. in height Hab. 

 Pond water, in the autumn. 



Pijxidium nutans, sp. nov., fig. 5. 



Body elongate-subfusiform, about twice as long as broad, some- 

 what gibbouSj widest centrally, tapering posteriorly to the pedicle, 

 slightly constricted beneath the truncate, finely crenulate peristome 

 border ; cuticular surface smooth ; ciliary disc consjiicuously and 

 obliquely exserted ; ciliary circles two, the second wreath extending 

 almost horizontally ; vestibiikim capacious, extending to near the 

 body centre, strongly ciliate, a long, curved, and consj^icuous vesti- 

 bular bristle present ; pedicle short, about one-fifth as long as the 

 body, variously and irregularly undulate ; contracted body obovate, 

 suddenly nodding, the posterior region inconspicuously invaginating 

 the anterior termination of the pedicle, and variously and irregularly 

 annulate, with an anterior snout-like projection. Length of body 

 1/450 in. Hab. Pond water; attached to the rootlets of floating 

 aquatic plants. Solitary. 



VorticelJa eonosoma, sp. nov., fig. 6. 



Body conical, soft and flexible, transversely striate, about four 

 times as long as broad, widest at the frontal margin, tapering thence 

 to near the attachment to the pedicle where it is continued as a 

 minute, subcylindrical prolongation, frequently showing at the begin- 

 ning of the posterior third a shght transverse constriction ; peristome 

 border everted, not revolute ; cilia short ; nucleus transversely placed 

 in the anterior body-half, short, broadly band-like, and much curved, 

 in certain positions of the body apparently ovate ; pedicle filiform, 

 from two to three times as long as the body, the muscular thread 

 distinct. Length of body 1/875 in. Hab. Attached to the gelati- 

 nous tubules of Conochilus volvox. 



This interesting form was first observed attached to the same 

 colonies of Conochilus which bore the Vorticella Conocliili, to be next 

 referred to, but in much less abundance, not more than two having 

 been noted on the same cluster of Eotifers. Although the muscular 

 thread is distinctly developed it seems seldom to exercise its contractile 

 power. 



The body when contracted becomes elongate-obovate, the trans- 

 verse constriction appears more distinctly marked, and the region in 

 advance settles back to a slight extent, and inconspicuously invaginates 

 this encircling depression in one or two folds. 



Vorticella Conochili, sp. nov., fig. 7. 



Body conical-campanulate, soft and changeable in shape, usually 

 somewhat gibbous, one and one-half times as long as broad ; trans- 

 versely striate ; peristome slightly narrower than the body centre, the 



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