OF THE KOLPODEA. 



635 



locomotion, and that each cilium is placed 

 upon a sort of little knob or articulated 

 base (see p. 285 ). (Fig. 329, a dried spe- 

 cimen ; fig. 330, a creature feeding upon 

 indigo, the particles of which around 

 indicate the currents produced by the 

 cilia ; fig. 332^ an ideal vieAv, to show 

 the structure of the nutritive organs as 

 stated byEhrenberg; fig. 331, a young 

 specimen, of the normal shape. ) Abun- 

 dant in vegetable infusions, and increases 

 so rapidly in stagnant waters that some 

 have referred their marvellous abmidance 

 to spontaneous generation from elemen- 

 tary primitive matter. 1-120" to 1-96". 



P. caudatum. — Spindle-shaped ; obtuse 

 anteriorly, attenuated posteriorly. Not 

 in infusions, but in ponds, amongst 

 decayed sedge-leaves and Confervae. 

 1-120". 



P. ClirysaJis Q>L) = PIeuronema eras- 

 sum (Duj.) (xxvi. 23). — Oblong and 

 cylindrical, equally rounded at both 

 ends ; cilia about the mouth very long. 

 This species, like P. Aurelia, is often 

 developed in such vast nmiads that the 

 water has a milky hue, the masses as- 

 cending or descending in the fluid : this 

 appearance may be produced by slightly 

 shaking the water. In infusions and in 

 salt water. 1-240" to 1-190". 



If the imiform length of the cilia be 

 admitted a generic character of Para- 

 mecium, this species, which has several 

 veiy long bristly cilia proceeding fi'om 

 the oral fissure, must be excluded. Both 

 Dujardin and Perty have proposed this, 

 and made Paramecium Clirysalis the re- 

 presentative of a genus styled " Pleuro- 

 nema.^^ 



It is usually fiUed \vith gi-eyish mole- 

 cules and vesicles, and rarely coloured 

 with chlorophyll. Fission longitudinal. 

 The long fibres from the lateral oral 

 fissures are from two to twelve in num- 

 ber, and, though frequently shorter, are 

 at times equal to or even much longer 

 than the body, and serve to vary its 

 movements by their activity. 



P. KoIpoclaiKolpoda Ren, M. ; K. Cu- 

 chUus, D.). — Ovate, slightly compressed ; 

 ends obtiL-^e, the anterior attenuated and 

 slightly bent like a hook. Found espe- 

 cially in infusions of Urtica dioica (the 

 stinging nettle). Perty is disposed to 

 believe this form to be an earlier stage 

 of P. Aurelia. 1-240". 



P. (?) Sinaiticum. — Elliptical, com- 

 pressed, the back and under side cari- 

 nated (keeled) ; frontal cilia indistinct. 

 Amongst Confervae, in a brook on Mount 

 Sinai. 1-288". 



P. (?) oratum. — Ovate, turgid; an- 

 teriorly attenuated and rounded. In 

 stagnant river-water. 1-288". 



P. compressum (Bursaria Lumhrici, 

 Stein). — Elliptical or reniform, com- 

 pressed. An oblique ^Teath of long 

 cilia reaches to the middle, where the 

 mouth, with its slight tongue-like pro- 

 cess, is situated. Found in the river- 

 mussel {Ml/a), and in the intestine of 

 the earthworm (Lambricus). 1-240" to 

 1-210". 



Dujardin takes this species as the type 

 of a newly-formed genus, " Phujiotoma,'''' 

 characterized especially by its com- 

 pressed lameUar figure, and by its para- 

 sitic habitat. Its cilia are described as 

 disposed in longitudinal rows over the 

 surface (vide ante, p. 627). 



We agree with Stein that there is no 

 good reason for framing the genus Pla- 

 giotoma, as Dujardin has done, on the 

 characters of this animalcule. If it have 

 no mouth it should take its place among 

 the Opalince; and it is to be remarked 

 that though Dujardin clearly saw a deep 

 fold or fissure — a feature of Opalince — he 

 could not succeed in artificially feeding 

 the animal with coloured food. At all 

 events, it has certainly no right to a place 

 among Paramecia, since the crest of 

 longer cilia about the mouth-like fossa 

 refers it (supposing it to have a mouth) 

 to the Bursari(2. 



P. Ifih'um (CycUdiwn 3IiUum, M.). — 

 SmaU, oblong, trilateral ; rounded equally 

 at both ends. In coloured water the 

 body is seen vibrating. I-lloO". 



P. Bursaria = Loxodes Bursaria (Ehr.) 

 (xxrx. 25-34). — It is not a Loxodes, since 

 all its cilia are equal and similar, Ehr- 

 enberg being in error respecting the ex- 

 istence of a larger sort in the infundi- 

 bulum leading to the mouth. 



P. versutam Q<l\\)lQ-i:)= Bursaria ver- 

 nalis (?) (Ehr. ). — Perty revives this spe- 

 cies ; but Lachmann (A. N. H. 1857, xix. 

 215) thinks it unnecessary to do so, " as 

 there is scarcely any certtiinty in the 

 synonymy previous to Ehrenberg; and 

 we should never again introduce an older 

 specific name for an Infusorium if it has 

 a name given to it by Ehrenberg, even 

 when it is not improbable he may have 

 overlooked an older name.'' 



b. var. Alpina (Perty). — Smaller, 

 plaited, stouter and more cylindrical 

 than P. versa fum. 



P. f/riseolum (Perty). — Little trans- 

 parent, being filled with gre;\'ish mole- 

 cules ; border very delicate. Nine to ten 

 longitudinal plaits on the surface. Move- 



