210 THE VOYAGE OF H.M.S. CHALLENGER. 



Nephrodium (Eunephrodium) pennigerum, Hook. 



Nephrodium {Eunephrodium) pennigerum, Hook., Sp. Fil., iv. p. 82; Hook, and Bak., Synopsis Fil., 

 p. 292; Baker in Journ. Linn. Soc. Lond., xv. p. 107. 



Arrotj. — Tropical Asia from the Himalayas, southward through the Archipelago, and 

 also in Tropical Africa. 



Polypodium (Dictyopteris) difforme, Blume. 



Pol>jpodium (Dictyopteris) difforme, Blume; Hook, and Bak., Synopsis Fil., p. 318; Baker in Journ. 

 Linn. Soc. Lond., xv. p. 108. 



Arrou. — Apparently restricted to the Archipelago and Polynesia. 



Polypodium (Niphobolus) macropodum, Baker. 



Polypodium (Niphobolus) macropodum, Baker in Journ. Linn. Soc. Lond., xv. p. 108. 



Rhizome woody, short-creeping, a line thick, clothed with minute, adpressed, deltoid, 

 black scales witli brown border. Phyllopode 3-4 lines, clothed with scales, just like the 

 rhizome. Proper stipes bordered very nearly to the base. Fronds all alike (barren and 

 fertile), ligulate, very thick and rigid in texture, 4-8 inches long, h to f broad, the 

 fertile portion contracted, the point acute, the base narrowed very gradually, the upper 

 surface naked, the lower clothed with thin cottony tomentum, like that of Polypodium 

 adnascens. Veins entirely hidden. Sori like those of Polypodium adnascens, occupying 

 continuously the contracted upper half of the fronds, minute and immersed in the pale 

 brown tomentum, 6-8 in an erecto-patent row between midrib and edge, and each showing 

 distinctly on the upper side of the frond. 



Arrou. — Differs from Niphobolus adnascens, var. varius, by its much thicker and 

 more rigid texture, long phyllopode, and almost obsolete stipes. 



Polypodium (Niphobolus) pachydermum, Baker. 



Pohjpodiuni (Niphobolus) pachydermum, Baker in Journ. Linn. Soc. Lond., xv. p. 10S. 



Rhizome wide-creeping, 1 line thick, woody, flexuose, clothed with minute adpressed, 

 lanceolate, black scales, with a brown border. Phyllopode very short. Stipes naked, ^ to 

 1 inch. Fronds dimorphic ; the barren ones oblanceolate-oblong, obtuse, 1-2 inches long, 

 cuneate at the base, J? to £ inch broad ; the fertile ones ligulate, 3-4 inches long. Veins 

 quite immersed. Texture very thick and rigid, the upper surface naked ; the lower with 

 only a coating of minute stellate scales, visible under a lens, with a distinct bare space 

 round each. Sori occupying the upper half or two-thirds of the fertile fronds, superficial, 

 \ line broad, 6-S in an erecto-patent row between the midrib and edge. 



Ki. — Nearest typical Niphobolus adnascens, but much thicker and more rigid in 

 texture, with superficial sori as large as in Polypodium lingua, and only spaced lepidote 

 scales. 



