70 THE AMERICAN NATURALIST. [VoL. XXXV. 
poison, have been isolated from a considerable number of species 
regarded ordinarily as dangerous only in a minor way or merely sus- 
picious; and there seems little reason to doubt that much of the 
ambiguity attending fungi of this class comes from the conversion, 
in their incipient decay, of a minor and perhaps scanty poisonous 
substance into a much more dangerous one, so that personal idiosyn- 
crasy or differences between individuals in strength of heart action 
seem capable of accounting for the divergence of opinion as to the 
edibility of a number of the dangerous species, like Boletuses, 
Gyromitra esculenta, certain Russulas, Lepiota morgani, and, indeed, 
the Amanita muscaria itself. dw 
North-American Pteridophytes. — A sixth edition of Professor 
Underwood's handbook of the ferns and fern allies occurring north 
of Mexico, which appears to have been carefully revised, has 
recently appeared and is likely to meet with ready sale. In it are 
incorporated records of the occurrence in one flora of several species 
not before recorded for it, and descriptions of several species regarded 
as new toscience. The author's recent comprehensive investigations 
of the priority status of generic names in the ferns have been con- 
sistently followed up in this book by the rehabilitation of the well- 
known species of Cystopteris in the genus Filix, and of what has 
been known as /echnum (or Lomaria) Spicant in the genus Struthi- 
opteris, while Aspidium is now replaced by Dryopteris, Polystichum, 
Phanerophlebia, and Tectaria. 1. 
Notes. — An interesting note by Professor Kellerman, on an Ohio 
station for Cissus ampelopsis or Ampelopsis cordata, with illustrations, 
appears in the first number of a new journal, Zhe O. S. U. Naturalist, 
published by the biological club of the Ohio State University, which 
also contains a list of additions to the Ohio flora, notes on collecting 
and preserving microscopical plants, and a paper by Kellerman on 
a foliicolous form of Ustilago reiliana, which species is believed to 
possess the characters of Cintractia rather than of Ustilago proper. 
Viola alabamensis, a new purple-flowered acaulescent species, is 
described by Pollard in a recent issue of Proceedings of the Biological 
Society of Washington. | 
A revision of the Cactacez of Paraguay, by Schumann, is being 
published in current numbers of the Monatsschrift für Kakteenkunde. 
1 Underwood, L. M. Our Native Ferns and their Allies, with Synoptical 
Descriptions of the American Pteridophytes North of Mexico. New York, Henry 
Holt & Co., 1900. x + 158 pp., 35 ff., and frontispiece plate. Price, $1.00. 
