156 BRITISH FRESHWATER BHIZOPODA. 



often pass into them. The examples found were 

 destitute of green colouring matter. 



Genus 30. AMPHIZONELLA Greeff; 1866. 



Corycia DujaBdin ? in Ann. Sci. nat., Zool. (3) XVIII 



(1852), p. 241. 

 Amphizoiiella Geeeff in Arch. mikr. Anat. II (1866), p. 323. 



Envelope membranous, thin and supple near the 

 mouth, presenting a double marginal contour, the 

 inner — representing the periphery of the envelope — 

 smooth and well defined ; the outer much finer, and 

 serrulate ; the plasma dense and uninuclear ; the 

 pseudopodia blunt, digitate, radiating in a greater or 

 less degree from the inverted mouth. 



1. Amphizonella violacea Greeff. 



(Plate XXXI, fig. 20.) 



Artifliizonella violacea Geeepf in Arch. mikr. Anat. II 

 (1866), p. 323, t. xviii, ff. 12-1.5; and in Sitzber. Ges. 

 Nat. Marburg, 1888, p. 98 ; Aechee in Q. Jrn. Micr. 

 Sci. (n.s.) XVII (1877), p. 464; Leidt ? Freshw. Ehiz. N. 

 Amer. (1879), p. 291 ; Blochmann Mikr. Thierw. Siisswass. 

 (1886), p. 11, t. i, f. 12; and ed. 2 (189.5), p. 14, t. i, 

 f. 8; Maggi in Arch. Ital. Biol. X (1888), pp. 18-5, 189; 

 Penaed in Mem. Soo. Geneve, XXXI (1890), 2, p. 132, 

 t. iii, ff. 9-11 ; Faune Rhiz. Leman (1902), p. 166, ff. 1-4 

 (p. 167) ; and in Rev. Suisse Zool. XIV, 2 (1906), p. 110, 

 t. iv, ft. 1-3; Peowazek in Arb. zool. Inst. Wien, XII, 3 

 (1900), p. 14. 



Test patelliform, round in lateral view, and sus- 

 ceptible of little change except at the mouth where 

 the membrane is thinnest; violet-tinted ; the fine outer 

 margin delicately serrulate, enveloping the test and 

 about equidistant from it (merging into it only on each 

 side of the mouth) ; the plasma dense, granular, con- 

 taining besides chlorophyllous corpuscles and granular 



