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THE ESSEX NATURALIST.
from nearly spherical to elongated ovoid, usually rather thick-
Walled, structureless, more or less translucent and without
adhering particles, in general reminding one very strongly of
certain species of Trachclomonas. Mouth with slightly thickened
lips, sometimes blocked with a plug of secreted material. Proto-
plasm usually containing many small granules and globules, but
no recognisable organic food particles, its circulatory movements
very slow. Nucleus large, with a broad clear outer zone, often
visible without the aid of reagents. Contractile vesicles one or
two, but often absent. Pseudopodia lobose, hyaline. It is a
remarkably inactive organism, at least under the conditions of
examination obtaining in the present case. Of the many living
specimens seen, only three exhibited actively extended pseudo-
podia. Very frequently, however, there was a mass of debris
attached to the mouth, held together apparently by some
exuded gelatinous (? protoplasmic) material. As usual with the
testaceous Rhizopods, the majority of the tests seen were either
empty or contained only extraneous matter.
Nebela. The commonest species was N. collaris, with N.
lageniformis a good way behind. N. militaris was seen in three
samples and a small form, N. parvula (?) twice.
Quadrula. Q. irregularis, seen only in one sample.
Heleopera. The usual species was H. sylvatica, but H. sphagni
and H. Petricola were also seen on one or two occasions.
Cochliopodium. C. bilimbosum was recorded once and C. actino-
phorum once. On two occasions a form not properly identified,
but probably C. vestitum, was seen.
Euglypha. A good many species of this genus were found, the
commonest being E. ciliata, E. denticulata and a small form,
E. laevis(?). E. strigosa was not unusual, but E. bryophila and
E. filifera (?) only occurred once or twice.
Assulina. The only species was A. muscorum, but it was
found in many samples.
Sphenoderia. The characteristic species was S. dentata, seen
in numerous samples. S. lenta and S. fissirostris were only
recorded once.
Trinema. The three common species of this genus were
nearly always present, T. enchelys and T. lineare in nearly every
sample and T. complanatum not far behind.
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