Zoology. 241 
D 
IL. Heliozoa, III. Radiolaria, IV. 
agreeing in this with the views of Professo 
of these two groups, excepting one Foraminifer, named by Leid 
a 
Foraminifera in that it is represented by several species inhabiting 
both salt and fresh water. The Protoplasta include the genera 
meeba, Difflugia, Nebela, Arcella, and others ; and the Heliozoa, 
Actinophrys, Heterophrys and others allied, With regard to 
onera he says, “though Professor Heckel has indicated and de- 
scribed a number of fresh-water species, I am not sure that I 
have had the opportunity of finding any of them, excepting per- 
haps the genus Vampyrella of Cienkowski, which he ascribes to 
the same order.” 
f bjects : f 
“Fresh-water Rhizopods are to be found almost everywhere in 
i not too m 
positions kept continuous! or wet, an uch 
haded. They afe especially frequent and abundant in compara- 
tively quiet waters ; clear, neither too cold, nor too much 
| 
heated by the sun, such as lakes, ponds, ditches, and pools. They 
be Ww al 
depressions and fissures of rocks, in the mouths of caves, among 
ate 
almost universally devoid of life of any kind. ; 
aR izopods also occur in the flocculent materials and slimy 
matter adherent to most submerged objects, such as rocks, the 
dead boughs of trees, and the stems and leaves of aquatic plants. 
