AMGEBA PROTEUS. 45 
DER in Acta Soc. Fauna Fenn. XII (1894), no. 2, p. 8; 
Ravmeer in Arch, f. Entwick. VIT (1898), p. 169, f. 29: 
Srenroos in Acta Soc. Fauna Fenn. XVII (1898), no. 1, 
pp. 32, 85 ; Scuent in Sitz.-ber. Ges. Miinchen, XV (1899), 
p. 90; in Festsch. C. von Kupffer (1899), p. 569, t. li; 
and (abstr.) in Amer. Nat. XXXIV (1900), pp. 332, 441; 
Zacwarias in Biol. Centralbl. IX (1899), p. 58; Catxins 
Protozoa (1901), passim, ff. 10a, 17a, 49, and in Amer. 
Nat. XXXV (1901), p. 645, etc.; Issn in Atti Soc. 
Torino, XXXVI (1901), p. 68, and in Atti Soc. Ligust. 
XIT (1901), p. 146; Masrermaw Zool. (1901), p. 85, £. 27 ; 
G. 8. West in Journ. Linn. Soc., Zool. XXVIII (1901), 
p. 3809, and op. cit. XXIX (1903), p. 109; Sroze in Zeits. 
Allg. Physiol. I (1902), p. 209. 
Amba communis Duncan in Pop. Sci. Rev. XVI (1877), 
p. 238, tt. v, vi. 
Ameba chaos Livy in Proc. Acad. Nat. Sci. Phil. 1878, p. 99. 
In general aspect, as well as in size, extremely 
variable; endoplasm colourless or greyish granular, 
frequently containing desmids and other chlorophyllous 
algze, or their remains, which have been incepted as 
food, also numerous refringent globules of variable 
size, and minute crystals of (apparently) calcium car- 
bonate. Body when at rest irregularly spherical, or 
ovoid; but in motion exhibiting a tendency to differen- 
tiate into anterior and posterior extremities—lobate 
expansions being protruded anteriorly—or to form 
digitate pseudopodia, which sometimes develop short 
lateral branches; the posterior extremity often ter- 
minating in a protuberance, expansion, or mulberry- 
like bulb. Pseudopodal movements frequently very 
active; at times sluggish. The contractile vesicle 
(usually single) situated behind the nucleus, which is 
ovoid, with a punctated surface, and usually large and 
conspicuous. 
Dimensions: Frequently 200» in diameter in the 
globular form, 300 x 150 when ovoid; radiate or 
dendroid, palmate, and cylindroid forms varying from 
05 mm. to 1 mm. according to Leidy. Elongate 
variety (Pl. III, fig. 2), 400-450 p. 
