ICONES FILICUM SINICARUM 



17 



k PLATE 9. 



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POLYSTICHUM DUTHIEI (Hope) C. Christensen 



POLYPODIACEAE 



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POLYSTICHUM DUTHIEI (Hope) C. Chr. Ind. 72 (1905), 581 (1906); Medd, Goteb. Bot. Tradg 

 ; 1:94 (1924); Hand-Mzt. in Symb. Sine. vi. 26 (1929). 



Aspidium duthiei Hope in Journ. Bomb. Nat. Hist. Soc. 12: 532, t. 6 (899). 

 Polystichum glaciate Christ in Bull. Soc. Bot. Fr. 52. Mem. 1. 28 (1905). 

 S or olepidium glaciate Christ in Bot. Gaz. 51:350 c. fig. (1911). 



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Rhizome thick, erect, densely rooted; leaves tufted (4-7 together), s^s 5 cm. 

 long, covered with dense dimorphic scales, the one short, fibrillose, the other broad, 

 ovate, acuminate, 6 mm. long, ochraceous-yellow; /ro^d 12-25 cm. long, 1.5-2.5 cm. broad 

 at the middle, linear-lanceolate, tapering to both ends, simply pinnate, rachis thickly 

 clothed with lanceolate subulate scales; pinnae conferted, the lower ones much reduced, 

 ovate, 4 mm. long, the middle ones to 1.2 cm. long, oblong, equal, margin strongly re- 

 flexed, crenate, truncate or cordate at the base; texture thick coriaceous, greenish- 

 flavescent, villose with whitish adpressed setaceous scales above, the under surface cloth- 

 ed in dense large lanceolate brown scales from the costa and the smaller ones from the 

 veins, the scales lanceolate-linear, scarious, 2 mm. long; veins entirely hidden, forked or 

 subpinnate near the base; sori 3-4 on each side of the costa, almost rounded, hidden, 

 inducium large, thin, brown, very fugaceous. 



Distribution: Yunnan, Szechuan, also N. W. India. 



Hope's type from N. W. India was a much smaller plant than the plant from W. 

 China. In general habit, this species resembles P. lachenense (HK.) Bedd., differs in 

 much shorter stiff stipe and stouter rachis, the dense covering of disproportionally large 

 scales, the adpressed white setae on the upper surface and thick coriaceous texture. Its 

 first record from China was credited to Pere Delavay, who found it in 1884 a * * ne foot 

 of a glacier in Su-kiang, Yunnan, for which reason, Christ called the plant P. glaciate 



by referring to Hope's P . duthiei, to which it was finally reduced by Dr. Christensen. 



Plate 9. Fig. 1. Habit sketch (natural size). 2. A pinna from middle part of the frond, upper 



side (x 4). 3. The same, under side (x 3). 4. The same, showing venation and attachment of sori. 



5. A portion of the pinna, showing receptacles of sori with a few scales attached (x 15.). 6. Scale 



from the under side of pinna (x 16). 7. Scale from rachis (x 16). 8. Smaller scale from the rachis 



(x 16). 9. Scale from the upper side of the pinna (x 16), 10. Scale from lower part of the stipe 

 (x 16). 



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