98 BRITISH FEESHWATEE BHIZOPODA. 



2. Corythion pulchellum Penard. 

 (Plate XL VIII, figs. 19-22.) 



? Euglypha minima 



Pbrty Kennt. Heinst. Lebensf. (1852), p. 187, pi. viii, f. 20. 

 Corythion pulchellum 



Penard in Mem. Soc. Geneve, XXXI, i, ii (1890), p. 189, pi. ix. 

 fe. 27-36; in Jaln-b. nassau. Ver. Naturk. XLIII (1890), p. 72; in 

 Amer. Natur. XXY (1891), p. 1081 ; Paune Rhiz. Leman (1902), 

 pp. 532-533, 4 figs.; in Arcli. Protist. II (1903), p. 272; Saroodines in 

 Cat. Invert. Suisse (1905), p. Ill ; in Arcli. Protist. IX (1909), p. 265. 



AvBBiNTZEPF in Trudui S.-Peterb. Obshch. XXXVI, ii (1906), p. 315. 



ScHOUTBDEN in Ann. Biol, lacustre, I (1906), p. 372. 



Hbinis in Avcb. Hydrobiol. V (1910), p. 111. 



Bbown in Ann. Scott. Nat. Hist. 1911, pp. 229, 230; in Naturalist, 

 1912, p. 112 ; in Scott. Natur. 1912, p. 181 ; 1913, pp. 208, 210. 



Wailes & Pbnabd in Proc. B. Irish Acad. XXXI, lxv (1911), pp. 

 15, 60, 61, 62. 



Wailbs in Scott. Natur. 1912, p. 60 ; in Jrn. Linn. Soc, Zool. XXXII 

 (1912), p. 126 ; in Naturalist, 1913, p. 147. 

 Choryihion pulchellum 



AvBEiNTZBPi' in Zool. Anzeig. XXXI (1907), p. 311. 



Test small, hyaline, in broad view oviform, mode- 

 rately compressed, truncate at the anterior extremity ; 

 in narrow view rounded posteriorly and tapering 

 sharply towards the aperture ; transverse section oval ; 

 aperture oblique, narrowly lenticular ; plasma clear, 

 colourless, with few granules ; nucleus containing a 

 single nucleole placed posteriorly ; two or three con- 

 tractile vesicles usually present; pseudopodia unknown. 



Length 26-35 ju.; breadth 15-20 /a; aperture 7- 

 lOju-; by- 3-4 /x in width; thickness about two thirds 

 the breadth. 



Habitat. — Mosses and sphagnum. 



Never very numerous, G. pulchellum is widely dis- 

 tributed. The test is so transparent that it is easily 

 overlooked and the small plates of which it is formed 

 are difficult to distinguish without special preparation. ■ 



In this species, as also in the preceding, a small 

 filament is sometimes observed situated near the aper- 

 ture ; it is always comparatively short, of a tough 

 nature, and appears as if it might be used for attaching 

 the test to some object. 



