Jan., 1921 
The Queensland Naturalist. 
Ill 
and Filosa, the terms being self-explanatory. As the name 
implies, these organisms are provided with a shell or test, 
in which a wonderful diversity of form and structure is 
exhibited in the various genera. 
In regard to material, the best results are obtained 
from squeezings of water plants and sphagnum, as well as 
the fiocculent sediment found at the ])ottom of pools; to 
the samples a few drops of 40 per cent, formalin should 
be added for preservation (1:20). 
Between twenty and thirty si)ecies are found round 
Brisbane ; most of these are comparatively common, and 
some, such as Arcella vulgaris, at certain periods of the 
year are exceedingly abundant; on the other hand, 1 have 
observed CgpJfoderia ampulla on only one occasion. 
Material may be obtained from numerous localities 
around Brisbane, and most of the pools wall furnish speci- 
mens of Arcella, Centropyxis, Difflugia., Euglyplia, and 
Trinema. One of the best ponds I have yet examined is a 
lagoon in the Brisbane Botanic Gardens, near the old bird 
hou.se. Foi' some specie.s preferring a sphagnous habitat, 
pools and drains on the site of the Sunnybank swamp have 
provided excellent specimens of Nebela caudata, Asstfliiia 
mtfscorwm, Euglypha cornpressa, and Campascus triqueter 
(see plate). 
In the plate is portrayed a number of the commoner 
species met with round Brisbane, and it is hoped that it 
may prove to be of some assistance to those interested in 
the subject; the numbers in brackets refer to the figures 
in the plate. 
ORDER LOBOSA. 
Genus Arcella. — Test more or less hemispherical; chitinoid ; 
exhibiting hexagonal, areas under high powers. 
1. A. vulgaris, Ehr. (1), comparatively small and hemi- 
spherical, usually plain but often facetted. 
2. A. mitrata (2) Ldy., larger than A. vulgaris and usually 
facetted or gibbose. 
2. A. artocrea (3), Ldy., test provided wdth a rim. 
4. A. discoides (4), Ehr., flattened and disc-like. 
Genus Diffiugia . — Test composed of sand grains, or chitin 
and sand grains. 
1. D. ohlonga, Ehr. (12), test pyriform. 
2. D, acuminata, Ehr. (10), test constructed of large 
grains; sharply pointed with no demarcation betw'een 
spine and body of test. 
3. I), cornuta, Leidy (13), similar to D. ohlonga, but the 
rounded base or fundus is provided wdth a spine. 
