Synopsis and Definitions of the Classes and Orders. 



A. PROTOZOA. 



Class I. Rhizopoda Protozoa without a cell wall, moving by 



pseudopodia. 



Order 1. Protoplasta Fresh water rhizopods fomid crawling 



over submerged objects, and on damp 

 bog-moss, either naked or enclosed by a 

 shell made of chitinous plates, sand 

 grains, etc., with one large opening, out 

 of which the animal extends its pseudo- 

 podia. 



Sub-order 1. Protoplasta lobosa.. With thick, generally rounded pseudo- 

 podia, if Amoeba. Difflugia, 



Sub-order 2. Protoplasta filosa . . With fine, thread-like pseudopodia. 



-kEnnhjpha. 



Order 2. Heliozoa Free-swimming fresh water Rhizopods, 



radiate in structure and often possessing 

 a silicious skeleton, but without central 

 capsule, if Actinoplirys, Clathrulina. 



Order 3. Radiolaria Marine Rhizopods. with radiate, silicious 



skeleton. Protoplasm divided by a cen- 

 tral capsule into extra- and infra-capsular 

 plasm, if Polycystina. 



Order 4. Foraminifera Marine Rhizopods. with calcareous shell, 



perforated with very numerous minute 

 openings {foramina) through which the 

 animal projects its fine pseudopodia. 

 ifCUohigeriiia, etc., in deep-sea dredg- 

 ings. 

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