AM(EBA VILLOSA. 51 



In size rivalling the larger forms of Amoeba proteus, 

 sometimes attaining, according to Wallich, a diameter 

 of one-fiftieth of an inch. The body, at its posterior 

 extremity, has a villous discoid or lobed protuberance, 

 which, whilst capable of modification within certain 

 limits, is persistent. Its precise function, however, is 

 not evident. In all other respects the animal closely 

 resembles, even in the young state, the larger forms of 

 A. proteus. The nucleus and contractile vacuole are 

 normally in the posterior region, the former ovoid 

 and punctated like that of A. proteus, the punctula- 

 tions being disposed longitudinally. Locomotion is 

 effected by lobular expansions of the ectoplasm, 

 anterior or lateral, or by digitate pseudopodia, which 

 may emerge on one side (with the result of altering 

 the line of progression) or from all sides at once, when 

 the appearance shown in PL II, fig. 2, is presented. 

 The villous appendage does not appear to be affected 

 by any pseudopodal movements. The colour of the 

 endoplasm is usually a creamy-white, greyish in the 

 denser parts, granular, and containing green and other 

 corpuscles resembling those observed in A. proteus, 

 and not infrequently also desmids and other algas. 



Dimensions variable ; elongated examples often 

 attaining a length of 250 /u, or more. 



Ponds at Hampstead, 1863 (Dr. Wallich); in similar 

 situations in Cheshire ; in the Rossendale district of 

 Lancashire (./. E. Lord) ; near Bingley, West York- 

 shire (G.S. West). 



Amoeba villosa was first detected by Dr. Wallich in 

 India, and he published a description of it in the 

 ' Annals ' (I. c.) in the year 1863. Returning to England 

 he found it at Hampstead. We suspect, however, 

 from Mr. H. J. Slack's description of some examples 

 from the last-named locality, in the ' Intellectual 

 Observer,' Vol. Ill, p. 430, that the much larger and 

 coarser-looking organism, Pelomyxa villosa Leidy, 

 was mistaken for it. The two species may have been 



