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CLASS SARCODINA. 
SUB-CLASS RHIZOPODA. 
Order I. AMCBINA. 
Family 1. Lososa. 
Naked Rhizopods, with lobose, or more or less digi- 
tate, elongate, sharply pointed or blunt pseudopodia, 
or, in place of these, and serving the purpose of loco- 
motion, wave-like or hernia-like expansions of the 
ectoplasm, 
SYNOPSIS OF THE GENERA. 
Plasma-body naked (in one species clothed with fine 
spicules) ; in size very variable; pseudopodia digitate 
and extensile, or taking the form of lobate, wave-like, 
or hernia-like expansions ; nuclei one or more (usually 
single); contractile vacuole mostly single. 1. Amwba. 
Pseudopodia radiate, rigid when at rest, often for 
considerable periods, widely extensile, blunt at the 
apex and linear, or tapering to a fine point; straight 
or curved, sometimes bent at an angle, or spirally 
twisted. Uninuclear. Contractile vacuole usually 
conspicuous. 2. Dactylospherium. 
Flagellate, the single flagellum extended in front 
during progressive movement of the individual; the 
plasma-body and pseudopodia, in adult examples, 
habitually covered with fine, hardly perceptible bacilli- 
form spicule, or naked. Uninuclear. 
3. Mastigameba. 
Plasma-body naked, multinucleate ; contractile vacu- 
oles inconspicuous ; pseudopodia lobular or wave- -like, 
