nt
paucity. They may be common, but none the less seldom seen. The
comatrichas afford an illustration. There are several very small
species. _C. pulchella_, _C. laxa_, _C. ellisii_ may be mentioned. _C.
pulchella_ has been studied nearly a hundred years and has a synonymy
accordingly. In 1875 Rostafinski in the material, and among the
descriptions, thought he recognized two distinct forms, and went on to
give them names; the first in honor of Persoon, _C. persoonii_, should
show an ovate or ovate-cylindric outline with acuminate tip; the second
should be truncate and represent a type first described by Berkeley
under a name given by Babington, _C. pulchella_. Berkeley's drawing
shows a sporangium with tip acuminate! Lilac or violaceous tints
attracted attention in the spores of _C. persoonii_ only; in _C.
pulchella_ all is ferruginous. Curtis is especially commended for
noticing the fact in describing _S. tenerrima_, here included as we see.

_Comatricha gracilis_ Wing. is slender, cylindric and has small spores
hardly reaching 6 mu; should perhaps be now set out as a separate
species; it is evidently purely an American phase.

Our figures, Plate XII., 16 and 16 _a_, 18 and 18 _a_, show _C.
pulchella_ and _C. gracilis_, respectively, extremes. Plate XIII., 4,
shows an ovate form not very unusual. This and _C. gracilis_ occur on
living leaves.

_C. ellisii_ is another of this minor series, very constant in its
delicate beauty, but approaches _C. nigra_ rather than the others here
discussed.

_C. laxa_, as the name implies, shows an open construction, suggested,
perhaps, by Rostafinski's photographic print, but better brought out by
Celakowsky, _Myx. Boehm._, Tab. 2, Figs. 7 and 8.

e. It has been shown[40] that the process of cell-division in the
spore-plasm of the myxomycete is not dissimilar to that obtaining under
the same conditions in higher plants. On this supposition we have
explanation of spore-division in _Ceratiomyxa_ and can understand the
adherence of spores now and again notable. Once the latter phenomenon
was thought peculiar to the genus _Badhamia_; but the unsculptured
epispore of the spores of reticularias, tubiferas, etc., suggest the
same thing and more recently we find it in _Dianema_ and in the
_Stemoniteae_; even _Stemonitis_ arrives with clustered spores in groups
of four, and we are in sight of a generalization wide.

It is interesting to note that something of this sort was observed by at