DIFFLUGIA. 11 



longation to the margin of the mouth. Nucleus single, 

 near the fundus of the ectosarc. Contractile vesicles 

 several, contiguous to the nucleus. Pseudopods, as 

 many as six or more, cylindrical, simple or branching, 

 commonly rounded at the ends, sometimes spreading 

 and pointed. 



Synopsis of Species of Difflugia. 



PAGE. 



Shell spherical or oval, Globulosa, 11 



Shell pyriform or pear-shaped, Pyrtformis, 12 



Shell amphora-form, fundus obtuse, occasionally 



with spines, neck short, mouth circular and 



usually everted, terminal, Urceolata, 13 



Shell goblet-shape, body spheroidal, neck wide, 



cylindroid, mouth terminal, Crater a, 13 



Shell amphora-form, or pyriform, fundus acumi- 

 nate or prolonged into a nipple, rarely with 



two or three points, Acuminata, 13 



Shell ovoid, or nearly spherical, composed of 



sand-grains, mouth lobed, Lobostoma, 14 



Shell hemispheroidal, usually yellowish chitinoid, 



base inverted, mouth trilobed, Arcula, 14 



Shell spherical, with hollow conical spines, 



mouth crenulated, Corona, 15 



Shell laterally ovoid, fundus prolonged obliquely 



upward, mouth inferior; long axis of shell 



oblique when animal is erect, Constricta, 15 



Shell with a partition dividing neck from body, 



giving it the appearance of a spiral, Sptralis, 16 



Diffiugia globulosa. SYN. : D. globulosa, Duj.; D. protei- 

 formis, Ehr. and Wallich ; D. globularis, Wallich ; D. acropodia, H. 

 and L. 



Shell spheroidal or oval, mouth inferior, terminal, cir- 

 cular, usually truncating the shell ; sometimes protruding, 



