BOTANICAL INFORMATION. 279 
pen of Professor Presl, in which he describes the Hymeno- 
phyllacee as a natural order, distinct from Filices. The work, 
a pamphlet of 70 pages, is, however, chiefly occupied with 
the genera, into which the author has deemed it proper to 
divide this group. We had found it difficult to define with 
anything like precision the two genera Hymenophyllum and 
Trichomanes of Sir James Smith, but our author goes much 
farther. He divides the order into two Tribes, TRICHOMA- 
NOIDEJE (Trichomanes, Sm.), and HYMENOPHYLLOIDEÆ 
(Hymenophyllum, Sm.). The first of these (Trichomanoidez) 
is again formed into two sections: l. TRiCHOMANE;E, In- 
dusii limbus integer, patens v. erectus, truncatus v. repando- 
crenulatus; including 10 Genera: 1, Feea, Bory. 2, Hyme- 
nostachys, Bory. 3, Lecanum, Pr. 4, Cardiomanes, Pr. 
5, Trichomanes, Pr. 6, Ragatellus, Pr. 7, Cephalomes, Pr. 
8, Neurophyllum, Pr. 9, Microgonium, Pr. 10, Abrodictyum, 
Sect. II. DinvwocLossEx. Indusii limbus bipartitus ; 
including 3 Genera: 11, Didymoglossum, Desv. 12, Merin- 
gium, Pr. 13, Hemiphlebium, Pr. And Tribe II. Hymeno- 
PHYLLOIDE is divided into 6 Genera, viz: 14, Leptocronium, 
Pr. 15, Myrmecostylum, Pr. 16, Ptycophyllum. 17, Hymeno- 
phyllum, Pr. 18, Spherocionium, Pr. 19, Hymenoglossum, 
Pr. The work is illustrated by characteristic figures of the 
new genera; and here, as well as in the author's “ Péerido- 
logia," very slight differences in the venation, as well as in 
the several parts of the fructification, involucre, receptacle, 
capsules, are employed in the formation of generic characters. 
An Appendix contains diagnoses of several Hymenophyl- 
laceze, many of which I think will be found under other names 
m our Species Filicum ; and although it is not too late to 
Blve extracts of the characters as a supplement at the con- 
clusion of the genus Trichomanes in our next part, yet I fear 
I! would rather add to than diminish the difficulty of study- 
ing the species of this most lovely portion of the Ferns. If 
our views of what should constitute distinguishing characters 
ia Genus are at variance with those of this acute author, 
