CHAEACTEES ON TRIBES AND GENEKA. 133 



Type. Polyhotrya osmundacea, H. B. K. 

 Illust. Hook, and Bauer, Gen. Pil., t. 78, B; Schott. 

 Gen. Fil., t. 7 ; Moore Ind. Pil., p. 1, fig. 1 to 7 ; 

 J. Sm. Ferns, Brit, and For., fig. 37 ; Hook. Sj'n. 

 Fil., t, 7, fig. 60, c. d. e. 

 Obs. — I now restrict Polyhotrya to the species allied in 

 general habit to the original type of the genus, Polyhotrya 

 osmundacea, of which there are about ten all natives of the 

 West Indies and Tropical America. In general habit they 

 are allied to the Tcctaria section of Poh/sfichum, the fronds 

 of some of the latter being very similar in every respect to 

 those of P. osmumlaeea, and in Polystiohitm asoendens the 

 fertile fronds are contracted similar to those of Polyhotrya. 



* Fronds pinnate, •pinnm drntate, or piiinatifid. 

 Sp. P. plumbicaule {Baher Syn. Fil.) ; P. fractiseriale 

 (Ba.her Syn. Fil.) ; P. pubens, Kanze. 



** Fronds hi-tri-quadriinnuate. 

 P. acuminata Link, (v v.) ; P. caudata, Kze. ; P. nutans, 

 Kze. ; P. incisa, Linlc. ; P. osmundacea, H. B. II. (v v. i 

 (P cyrdindrica, Kaidf.) ; P. cauiculatum, Ivlot. ; P. Lech- 

 leriana, Mett. 



** Veins cortibined at the margin. 



49.— Olfersia. Badd. (18l!:<). 



Acrosticlmm, sp. Hook. Sp. Fil. 



Vernation uniserial, sarmentum thick, scandent, squamose. 

 Fronds pinnate, 1 to 3 feet long ; pinno3 ovate lanceolate, 

 adherent and oblique at the base, smooth coriaceous. Veins 

 uniform, simple, or forked, direct parallel, their apices 

 combined by a transverse marginal vein. Fertile pinnoe 

 linear or pinnatifid, convolute, wholly sporangiferous. 



