MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 55 
mit einem bleibenden, nach der Rippe der Lappchen zu sich neigenden Deckel 
éffnen. Nur Eine, wahrscheinlich baumférmige, Art, Cibotium Chamissoi, von der 
Siidsee.”’ 
In America the genus is apparently restricted to the northern con- 
tinent. The species may be distinguished by means of the following 
key: 
KEY TO THE SPECIES. 
Coste glabrous or readily glabrescent; leaf tissue conspicuously 
ceraceo-pruinose below. 
Sori mostly distant or subdistant, usually extending beyond 
the margin in the plane of the segment................ 1. C. schiedet. 
Sori contiguous to imbricate, appearing dorsal, i. e., not ex- 
tending beyond the margin. 
Lamina deeply tripinnatifid; veins 7 to 9 pairs to the 
segment; sori nearly parallel to the costule.....-. 2. C. regale. 
Lamina tripinnate or subtripinnate; veins 8 to 15 pairs 
to the segment; sori obviously oblique to the cos- 
tule, closer..........-------2-02 eee ee ee eeeeeee- 3. ©. quatemalense. 
Coste thickly invested with long persistent antrorse hairs; leaf 
tissue not obviously ceraceo-pruinose below......-....---- 4. C. wendlandi. 
1. Cibotium schiedei Schlecht. & Cham. Linnaea 5: 616. 1830. PLATE 30. 
Dicksonia schiedei Baker in Hook. & Baker, Syn. Fil. 50. 1866. 
Tyre Locauity: Hacienda de la Laguna, Mexico, Schiede 801. 
DistRiBUTION: Humid mountains of Oaxaca and Vera Cruz, at 600 to 1,200 meters 
elevation. 
InLustraTIons: Presl, Tent. Pterid. pl. 11. f. 9. 
Cibotium schiedei, which was the first species of this genus to be described from 
North America, is apparently confined to Mexico.! It has long been in cultivation 
and need not be confused with any other. The fertile segments, especially the 
larger ones, are manifestly dentate-crenate and contain only 6 to 8 pairs of veins, 
of which the fertile ones are almost invariably simple and the sterile ones usually once 
forked at a slight angle. The most distinctive feature lies in the distant or subdistant 
produced sori (2 to 7 pairs) which commonly extend outward in the plane of the 
lamina, but in a few instances (in extreme age) are bent back under the segment. 
This character, while helpful in distinguishing the species, is possibly not fundamental 
and is, no doubt, correlated directly with the thin, chartaceous leaf tissue. In all the 
other American species the sori are closer and have the appearance of being erect 
and dorsal, since the segments, on account of their coriaceous or at least herbaceous 
texture, have the margins strongly revolute at maturity or in drying. 
The following specimens have been examined: 
Mexico: Hacienda de la Laguna, Schiede 801. San Francisco, Mirador, Lieb- 
mann. Orizaba, Miiller. Cordoba, Kerber 90a; Fink 13; Bourgeau 2378. 
Barranca de Tenampa, Zacuapan, Vera Cruz, September, 1906, C. A. Purpus 
1976. Zacuapan, Vera Cruz, November, 1908, C. A. Purpus 1976a. (Also 
numerous specimens from the Botanical Gardens of Kew, Berlin, and 
Leipsic.) 
EXPLANATION OF PLATE 30.—a, Pinnule from a cultivated plant, er hort. Lips.; 6, portion of pinnule of 
type collection (Schiede 801), in Underwood Fern Herbarium; c, pinnule from very old specimen of Purpus 
1976; d-g, Purpus 1976a, d representing one of the larger inferior pinnules, e and f two superior pinnules from 
near the base of the pinna (at a point opposite d), g a nearly sterile pinnule from near the middle of a pinna, 
Only a shows the upper surface, All are at natural size. 
! Skinner’s plant from Guatemala, referred here by Hooker, is C. wendlandi. See 
under that species, p. 57. 
