difficult to define that for the present I shall limit my record to
this brief notice. Size of shell 230µ by 270µ.


Genus ACTINOPHRYS Ehr.


The body is spherical and differentiated into granular endoplasm and
vacuolated ectoplasm, but the zones are not definitely separated.
There is one central nucleus and usually one contractile vacuole. The
pseudopodia have axial filaments that can be traced to the periphery
of the nucleus. Fresh and salt water.

Actinophrys sol Ehr., variety. Fig. 5.

Synonyms: See Schaudinn '95.

The diameter is about 50µ; the vacuolated ectoplasm passes gradually
into the granular endoplasm. This is the characterization given _A.
sol_ by Schaudinn, and it applies perfectly to the freshwater forms.
If I am correct, however, in placing an _Actinophrys_-like form
found at Woods Hole in this species, the description will have to
be somewhat modified. In this form (fig. 5) there is no distinction
between ectoplasm and endoplasm, and there is an entire absence of
vacuoles. The nucleus is central, and axial filaments were not seen.
The single specimen that I found looked much like a Suctorian of
the genus _Sphærophrya_, but the absence of a firm cuticle and the
presence of food-taking pseudopodia with granule-streaming makes it a
very questionable Suctorian, and 1 place it here until further study
throws more light upon it.