488 ORDER HOLOTRICHA. 



Paramsecium putrinum, C. & L. 



This species is described by Claparede and Lachmann as corresponding 

 in external form with Paramacium bursaria, but as differing from that 

 animalcule structurally by its non-possession of trichocysts and by the 

 presence of a single contractile vesicle only, which is situated near the 

 anterior body-half; the anal aperture is located on the ventral surface, 

 though not so far forward as in P. aurelia ; endoplast band-shaped, curved, 

 accompanied by an oval endoplastule. 



HAB. Stagnant water, among decaying vegetable matter. 



Paramsecium glaucum, C. & L. 



Body ovate or elliptical, rounded at each extremity, the anterior one 

 slightly the narrower, about twice as long as broad ; cortex enclosing tricho- 

 cysts ; colour glaucous green ; buccal groove longitudinal, the oral 

 aperture situated a little in front of the median line ; two posteriorly 

 situated, stellate, contractile vesicles. Length of body 1-147". 



HAB. Salt water : Norwegian coast (Claparede and Lachmann). 



Paramsecium marina, S. K. PL. XXXII. FIG. 9. 



Body elongate-ovate, subclavate, about five times as long as broad, 

 rounded and widest posteriorly, tapering and slightly curved in the anterior 

 region ; oral groove extending backwards to the centre of the body ; con- 

 tractile vesicle single, of large size, posteriorly situated ; endoplast ovate, 

 subcentral. Length 1-240". HAB. Salt water. 



This species was obtained in some abundance in the small rock pools refilled 

 only by the spring tides, at both Teignmouth and Anstey's Cove, South Devon, in 

 July 1879. The motion of the animalcules in these pools, as observed with the aid 

 of a pocket lens, was highly characteristic, consisting of progress backwards and 

 forwards for long distances, and in the same straight line, accompanied by rotation 

 on their longitudinal axes, after the manner of various Bacteria and Vibriones. 



Supplementary Species. 



The Paramadum inversum and P. ovale of Claparede and Lachmann are referable 

 to the genus Trichoda of Stein, while the Paramcecium microstomum of the same 

 authorities would appear to belong to the genus Isotricha. The Paramacium chry- 

 salis of Ehrenberg is now referred ^o the genus Pleuronema, and his Paramacium 

 colpoda to Colpidium. 



GENUS II. LOXOCEPHALUS, Eberhard. 



Animalcules free-swimming, persistent in shape, elongate-ovate or sub- 

 cylindrical, having an oblique constriction at a little distance from the 

 anterior extremity, and bearing in this region, on one or both sides, one or 

 more short, curved setae ; the anterior extremity somewhat obliquely truncate, 

 and bent slightly to one side ; one or more long, hair-like caudal setae 

 developed at the posterior extremity ; cilia of the cuticular surface fine, even 

 throughout ; endoplasm more or less granular and opaque ; oral aperture 

 ventral, subterminal, indistinct. 



