202 FEBSH-WATEE EHIZOPODS OF NOETH AMEEICA. 



filling the shell or slightly contracted from its sides ; when shorter than the 

 cavity of the shell, mostly adherent to the fundus by a pair of pseudopodal 

 threads. Nucleus large, clear, and usually homogeneous. Contractile 

 vesicles occupying an intermediate zone of the sarcode. Pseudopods nu- 

 merous, forking, radiating in any direction from the mouth, but mostly on 

 a horizontal plane, susceptible of a great variety of movement and change 



of form. 



CYPHODERIA AMPULLA. 



Plate XXXIV, figs. 1-16. 



Difflugia Ampulla. Ehrenterg: Berioht Preus. Ak. Wis. 1840, 199; Abh. Ak. Wis. 1871, Taf. iii, Fig. 11. 



? mfflugia Lagena. Ehrenberg : Abh. Ak. Wis. 1841, 413, Taf. iv, Fig. 11 ; 1871, Taf. ii, Fig. 2. 



Cyphoderia margaritacea. SeUumberger : An. So. Nat. 1845, iii, 255. — Fresouius: Abh. Senck. Naturf. 

 Ges. 1856-58, il, 225, Taf. xii, Fig. 28-36.— Stein : Sitzungsb. Bohm. Akad. 1857 (fide 

 Sohulze). — Carter: An. Mag. Nat. Hist. 1864, xiii, 33, pi. ii, fig. 18. — ^Hertwig and Lesser : 

 Arch. mik. Anat. 1874, x. Sup. 132.— Leidy: Pr. Ac. Nat. Sc. 1874, 227; 1877, 294.— Schnlze : 

 Arch. mik. Anat. 1875, xi, 106, Taf. v. Fig. 12-20. 



Eugh/plia curvata. Perty : Kennt. kleinst. Lebensformen, 1852, 187, pi. viii, fig. 21. 



Lagynis baltiea. Schultze : Organ. Polythalamien, 1854, 56, Taf. i. Fig. 7, 8. 



JSuglypha margaritacea. WaUich: An. Mag. Nat. Hist. 1864, xiii, 240,244,245, pi. xvi, fig. 48. 



Difflugia margaritacea. Wallich : Ibidem, 245. 



Muglypha baltica. Wallich: Ibidem. 



Difflugia Seelandioa. Ehrenberg : Abh. Ak. Wis. 1869, Taf. ii. Fig. 23. 



Ampullaria (Weraeck). Ehrenberg: Ibidem, 1871, 234. 



Difflugia adunca. Ehrenberg : Ibidem, 1871, 248, Taf. iii. Fig. 8, 9. 



? Difflugia alalamensia. Ehrenberg : Ibidem, Fig. 10. 



Difflugia uncmata. Ehrenberg : Ibidem, Fig. 13. 



Sologhjpha, sen D. AssuUna adunca, D. A. alabamenm, D. 2. Ampulla, D. A. margaritacea, D. A. nrwi- 

 nata. Ehrenberg : Abh. 1871, 246. 



Muglypha, sen D. Aasulina Seelandica. Ehrenberg : Abh. 1871, 246. 



Cyphoderia ampulla. Leidy : Pr. Ac. Nat. Sc. 1878, 173. 



Shell retort-shaped, with a short cylindrical neck curving downward, 

 and truncated by a circular mouth ; body of the shell oblong oval, with the 

 longitudinal axis, in the active or moving condition of the animal, more or 

 less inclined, but nearly horizontal ; fundus obtusely rounded, sometimes 

 flattened, frequently more or less prolonged or narrowed at the summit 

 into a nipple-like process. Color of the shell mostly yellowish, less fre- 

 quently colorless. 



/Si^e.— Ranging from 0.112 mm. to 0.176 mm. long by 0.04 mm. to 

 0.08 mm. broad, with the mouth 0.016 mm. to 0.028 mm. wide. 



Locality. — The superficial ooze of springs, ponds, lakes, and ditches. 

 Pennsylvania, New Jersey, Rhode Island, Florida, "Wyoming Territory, 

 and Nova Scotia. 



Cyphoderia ampulla has an oval oblong, retort-shaped shell, with a 

 short cylindroid neck curving downward to the mouth. See figs. 1-15, pi. 



