258 206 



costule. Sporangia with a few simple, deciduous setæ or in some specimens glabrous. 

 "In the early stage of growth trace of a rudimentary involucre is observable, 

 which however soon disappears" (Jenman loc. cit.). I have not found indusia. 



This species, of which the plate of Hk. Icon. t. 1669 gives a fair illustration, 

 can be considered the type of a small group including the species nr. 257 — 261 of 

 this monograph, which connect Ü. tetragona with D. Poiteana. From D. tetragona 

 they differ by venation and less cut pinnæ, from D. Poiteana by few or no meni- 

 scioid veins. The Central-American specimens of D. oblilerata approach D. Poiteana 

 more than the West-Indian ones, and they also resemble D. paucipinnata, from which 

 they differ by position of sori, venation, texture and generally exindusiate sori. 



D. obliterata is confined to Jamaica, Cuba, Mexico and Northern Central- 

 America. I have seen the following specimens: 



Jamaica: Swartz (H, S); Ma.von nr. 831, 1799 (- Underwood nr. 2772), 184G, 1924, 2876 (W^), 2375 



(C, W); Underwood nr 117 (W); Clute nr. 246 |W); Hart nr. 336 |\V); O. Hansen (CC, H). 

 Cuba: Wright nr. 1010 (C, CC, S, W) — Santiago, Poi-lard and E. & W. Palmer nr. 96 (W) — Pinar 



del Rio, Palmer and Riley nr. 72 iC, H, W), 2.')1 (W) — Santa Catalina, Caldwell and Baker 



nr. 7028 (W) — Isla de Pinos: A. H. Curtiss nr.345(W); A.A.Taylor nr.9(\V); Palmer 



and Riley nr. 1040 (W). 

 Me.xico: Barranca de Jovo, Liebmann (H B, P. faucium Liebm.) — Schaff.ner (B) — Coatzacoalcos, 



isthmus of Tehuantepec, Chas. L. Smith nr. 2052 (W). 

 Guatemala: Puerto Barrios, Maxon and Hey nr. 3059 (C, W) Rio Dulce, Donnell Smith nr. 1559 



(W) — Livingston, Kellermann nr. 4856 (W) — Puerto Barrios, B. I.. Robinson nr. 472 (W) 



— near Cacao, H. S. Barber nr. 186 (\V). 

 Honduras; Bonacca, Godman and Salvin (B) — San Pedro Sula, C. Thieme, ed. Donn. Smith nr. 5685 



(W); 5693 part. (B, not W). 



260. Dryopteris nigrescentia (Jenman) C. Chr. Ind. 279. 1905 — Fig. 44. 



Syn. Polgpodium nigrescentium Jenman, Gard. Chron. III. 17; 100. 1895; 

 Bull. Dept. Jam. n. s. 4: 132. 1897. 



Type from Jamaica, leg. Jenman (W!). 



A doubtful species, of which I have seen 5 leaves only. It may be an ab- 

 normal, local form of D. obliterata, which it resembles in the essential characters. 

 It differs by the stouter rhizome, smaller leaves (10 cm long and broad at base), 

 dark-green colour, wrinkled, serrulate, opposite and sessile pinnæ, and shortened 

 often rudimentary terminal pinna. Veins 4 — 5 to each side, the lowest 2 — 3 pairs 

 anastomosing. Sporangia glabrous. Rachis more conspicuously stellato-puberulous. 



261. Dryopteris Rolandii n. sp. — Fig. 45. 



Ecuador: Rio de Ventanas prope Guayaquil, leg. Spruce nr. 5718 (type in RB). 



Rhizomate? Stipitibus validis, brunneo-stramineis, supra trisulcatis, 6'/j dem 

 longis, ubique dense stellatim puberulis ad insertionem sparse squamosis; pilis bre- 

 vissimis 3 — 6 furcalis, squamis angustis pilis stellatis dense instructis. Lamina 

 4 dem longa, pinnata cum imparl, herbacea, pure viridi; rachi tenui stellatim pilosa; 

 pinnis 7-jugis, suboppositis vel superioribus alternis, sessilibus, inter se 5—6 cm 



