Clathrulina elegans, Cienkowsky, in Essex. 58
external spinulose membrane. After some time the cysts
develop nucleated and flagellated zoospores, which finally
pass through the Actinophrys-like and Clathrulina stages, as
in β. (δ) In this mode (as observed by Sara G. Foulke,
Proc. Acad. Nat. Sci. Philad., 1884) the Clathrulina with-
draws its rays and the protoplasm divides, as above mentioned
in section α, but the masses are smooth and transparent.
After a period of quiescence, each sarcode mass passed out of
the capsule, developed a flagellum, and swam freely about in
the water. "Finally it was seen to attach the top of its
flagellum to the glass and revolve swiftly for a few moments,
when instantly the whole body became spherical, rays were
shot out, and the transformed monad was in no point, except
that of size, to be distinguished from its Actinophrys-like
cousin." This reproduction by free-swimming monad-forms
may be of great service in securing a widespread distribution
of the species, and so preventing its destruction by the
dangers attendant upon a too-restricted habitat.
In addition to the references given in the above notes, the
reader will find information in Mr. Archer's papers in the
'Quarterly Journal of Microscopical Science' (1868-1877),
and in Journ. Roy. Microscopical Soc. for 1884 (Ser. ii.,
vol. iv., p. 402). It is to be hoped that those of our members
possessing the requisite microscopical powers will search for
Clathrulina in Essex, and endeavour to follow out the various
details of its reproduction and development, which are hardly
yet thoroughly understood, and which seem to be of very
great biological interest.—Ed.]