St BRITISH FRESHWATER RHIZOPODA. 
Ourwneba vorae Lemmy in Proc. Acad. Nat. Sci. Phil. 
1874, p. 78; op. cit. 1875, p. 127; and Freshw. Rhiz. N. 
Amer. (1879), p. 67, t. ix, ff. 1-12; Magar in Atti Soc. 
Ital. XIX (1876), p. 405; Parowa in Boll. Scient. I, an. 2 
(1880), p. 47; Hrrencock Synops. Freshw. Rhiz. (1881), 
p. 7; Perry in Proc. Amer. Soc. Micr. XII (1891), p. 94. 
OQurameba lapsa Lerpy in Proc. Acad. Nat. Sci. Phil. 1874, 
p- 78. 
Ourameba ARcHER in Q. J. Micr. Sci. XVI, nis. (1876), 
p. 887, and in Journ. Dublin Micr. Club, III, 2 (1877), 
p. 128. 
Ourainwba villosa Ray Lankester in Encycl. Brit. ed. 9, 
XIX (1885), p. S42. 
The peculiar caudal appendage, consisting of, usually, 
from one to three tufts of straight, rigid filaments, 
emanating from a common stalk, is the characteristic 
feature of this organism, distinguishing it at once from 
the larger forms of Anwba proteus, and also from A. 
rilluosr. The appendage is dragged behind, in the 
animal’s progress, and appears nut to undergo any 
modification. 
Dimensions: Length 140 w and upwards; caudal 
filaments about 180 p. 
Ireland (Archer, 1866). 
Mr. Archer was the first to record this organism as 
British. He exhibited it in 1866, at a meeting of the 
Dublin Microscopical Society, as a form of Amaba 
villosa, and subsequently, on the appearance of Pro- 
fessor Leidy’s work, in which it was treated as 
generically distinct, he adhered to his conclusions and 
dissented from those of the Professor, on the ground 
that the posterior processes were (as he believed) 
capable of retraction. Leidy found that, except in the 
possession of this peculiar appendage, Ourameba 
differed in no way from the larger specimens of Aiueba 
proteus; though m some instances the posterior part 
of the body assumed “a mulberry-like appearance, 
which simulated a patch.” Archer describes the pro- 
longations as “forming a compact bundle, linear, often 
