the Polish author has established. Especially is this true in the
case of organisms so very perishable and fragile as those now in
question where comparative revision is apt to result in uncertainty. We
had preferred to leave the Rostafinskian, _i. e._ the heretofore current
nomenclature, untouched; but since other writers have preferred to do
otherwise, we are compelled to recognize the resultant confusion.

Slime-moulds have long attracted the attention of the student of nature.
For nearly two hundred years they find place more or less definite in
botanical literature. Micheli, 1729, figures a number of them, some so
accurately that the identity of the species is hardly to be questioned.
Other early writers are Buxbaum and Dillenius. But the great names
before Rostafinski are Schrader, Persoon, and Fries. Schrader's judgment
was especially clear. In his _Nova Genera_, 1797, he recognizes plainly
the difference between slime-moulds and everything else that passed by
the name of fungus, and proposed that they should be set off in a family
by themselves,[2] but he suggested no definite name. Nees (C. G.) also
made the same observation in 1817, and proposed the name _Aerogastres_;
but he cites as type of his aerogastres, _Eurotium_, and includes so
many fungi, that it seems unsafe now to approve his nomenclature.
Schrader also has left an excellent account of the cribrarias, the basis
of all that has since been attempted in that genus.

Persoon, in his _Synopsis_, 1801, attempts a review of all the fungi
known up to that time. His notes and synonymy are invaluable, enabling
us to understand the references of many of the earlier authors where
these had otherwise been indefinite if not unintelligible. He makes a
great many changes in nomenclature, and excuses himself on the ground
that he follows, in this particular, illustrious examples!
Unfortunately, so do we all!

Fries, in his _Systema Mycologicum_, 1829, summed up in most wonderful
way the work of all his predecessors and the mycologic science of his
time. In reading Fries the modern student hardly knows which most to
admire, the author's far-reaching, patient research, the singular acumen
of his taxonomic instinct, the graceful exactness of the Latin in which
his conclusions are expressed, or the delicate courtesy with which he
touches the work even the most primitive, of those his predecessors or
contemporaries. Nevertheless in our particular group even the
determ