6 DAVENPORT ACADEMY OF SCIENCES. 



CHALARATHORACIDA. 



With an outer covering of separate silicious spicules. 

 DESMOTHORACIDA. 



With a perforated shell, sometimes stalked. 



Families and Genera of Amcebida. 



Amcebid.e. 



Without shells. Pseudopodia lobose or sharp-pointed, some- 

 times branched. 

 Amxba Ehr. 

 Dbiameeba H. & Iv. 

 ^^Hyahdiscns H. & L,. 



Round or disc-shaped, moving vvithovit distinct pseudopodia. 

 '^Pelomyxa GreefT. 



Broad lobe-like pseudopodia, many nuclei. 



ArCEIvLID.E. 



With membranous shells with which may be incorporated foreign 

 materials. Pseudopodia lobose or short-pointed, often branched. 

 Difflugia Leclerc. 

 Arcella Stein. 

 Centropyxis Stein. 

 Cochliopodiuni H. & I,. 

 Pamp/iagits Bailey. 

 ^Hyalosphoiia Stein. 



Shell flattened, pyriform, aperture terminal, pseudopodia 

 finger-like. 

 ^Oiiadi'ula Schultze. 

 Shell of square plates of chitir., flattened pyriform, pseudo- 

 podia finger-like. 

 '^Nebela L,eidy. 



Shell of chitinous plates of variable shapes and sizes often 

 intermingled with foreign materials. Pseudopodia as in Quadnda. 



Huglyphid/E. 



Shells of plates of chitin or silica, sometimes spined. Pseudo- 

 podia sharp-pointed, often branched but not anastomosing. 



