204 CHAEACIEES OF TRIBES AND GENERA. 



Sp. C. meniscioides. PrifsZ. {Willd.) ; G. confertum, Presl. 

 {Kaulf.) (v V.) ; C. abbreviatum, Presl. {Schnul). 



106.— CrRTOMiuM, Presl (1836). 

 Aspidiurii sp., Hooh Sp. FiJ. 



Vernation fasciculate, erect. Fronds 1 to 3 feet high, 

 pinnate, pinnre elliptical lanceolate, 6 to 8 inches long, 

 1 to 4 inches wide, falcate, more or less auriculated at the 

 base, the margin sub-entire or spinulose, veins two or 

 three times forked or pinnate, venules alternate, the lower 

 exterior branch free, the others acutely anastomosing, 

 producing from their junctions free or anastomosing vein- 

 lets. Beceptacles punctiform on or below the apices or 

 points of junction of the venules. Sori round, transversely 

 uniserial, or numerous and oblique serial. Indusium 

 orbicular. 



Type. Aspidimn falcatum, Stvartz. 



Illust. Hook, and Grev., t. 171 ; Hook, and Bauer, t. 49, 

 C ; Hook. Fil. Exot., t. 92 ; Moore Ind. Fil., p. 66 ; 

 J. Sm. Ferns, Brit, and For., fig. 68 ; Hook. Syn. Fil., 

 t. 5, fig. 43, c. 



Obs. — The few species constituting this genus agree in 

 general habit with the pinnate species of Polysticlmm, but 

 differ in having anastomose veins. I can find no character 

 of sufBcient value to retain Presl's genera PlianeropMebia 

 and Amhlia as distinct from Gyrtoniium, these two genera 

 being evidently founded on specimens off which the indu- 

 sium had fallen ; the only point that may give them an 

 appearance of genuine difference is, that the typical species 

 of Gyrtomium are Eastern, and those of the latter genera 

 "Western. 



Sp. C. caducum {Wall.) {Hemiyonum, J. Sm., 1841); G. 



