HYALODISCUS EUBICUNDUS. 107 



Vampyrella pedata KLE!N in Bot. Centralbl. VIII (1881), p. 

 321; op. cit.X (1882), p. 347; op. cit. XI (1882), pp. 204, 

 259, t. iv, if. 1-19 ; in Bot. Zeit. XL (1882), col. 216, t. ivA, 

 ff. 27-32 ; and in Biol. Centralbl. II (1882), p. 139* ZOPF 

 Pilzthiere oder Schleimp. (1885), p. 106, f. 38, v-viii; 

 BERTHOLD Stud. Protopl.-mech. (1886), pp. 95, 104, t. ii, 

 f. 1 ; DANGEARD in Ann. Sci. Nat,, Bot, (7) IV (1886), pp. 

 253, 255; BLOCHMANN Mikr. Thierw. Siisswass. ed. 2 

 (1895), p. 22, t. ii, f. 40 ; G. S. WEST in Journ. Linn. Soc., 

 Zool. XXVIII (1901), p. 334. 



Endoplasm finely granular, reddish, generally 

 occupying the central part of the discoid body, with 

 a highly-pellucid and broadish band of ectoplasm 

 extending all round, and changing form, within certain 

 limits, during the activity of the animal, sometimes 

 projecting short conical or acute pseudopod-like 

 prominences, but almost invariably, when progress is 

 not intercepted, preserving the discoid character. 

 Projections of the granular endoplasm, more or less 

 numerous, extend (mostly in fine lines) from the ill- 

 defined frontal margin of the endoplasm outwards to 

 the periphery of the ectoplasm, but not beyond, with 

 shorter and more variable ones intermixed. Posterior 

 margin of the endoplasm more sharply defined, and 

 destitute of the projections last mentioned. 



Dimensions: Length of hyaline disc 50-80 p; breadth 

 about 30 p. 



In ponds amongst surface-vegetation; Cheshire. In 

 the lakes at Capel Curig and in Lynn-y-cwm-ffynon, 

 North Wales (G. S. West). 



This species is evidently closely related to Vam- 

 pyretta vorax, but we have thought it right to preserve 

 Hertwig and Lesser' s generic name, on account of the 

 manifest peculiarities of the organism which those 

 authors were the first to point out. It appears, under 

 a moderate power of the microscope (to quote their 

 description), as an oval body, reddish-brown in colour, 

 gliding slowly along. Under higher magnification this 



