254 ACROSTICEIUM, § OLFERSIA. 



§ 7. Olfersia. — Fronds dimorphous, simple or pinnate. Veins simple or 

 forked, connivent within the margin, so as to form there a longitudinal, straight, 

 or zigzag veiii, sometimes producing short exeurrent veinlets. — Gen. Olfersia, 

 Raddi. Aconiopteris, Pr. — (Not a very natural group, but easily recognized 

 by the venation.) 



* Fronds ample, jjitinate or bipinnate. — Euolfersia. 



117- A. (Olfersia) cei'vinum, Sw. ; caudex short thick 

 creeping densely clothed with long narrow brown subulate 

 membranaceous scales, stipites approximate a span or more 

 long stout scaly at the base, fronds coriaceo-membranaceous 

 3-5 feet long ; sterile ones pinnated (when young quite sim- 

 ple) on long slender stipites, pinnae numerous 4-5-9-10 

 inches long 1-2 inches and more wide ovate or lanceolate 

 acuminate, the lateral ones very unequal-sided at the base, 

 the inferior base excised, the margin entire or a little serrated 

 at the apex, veins numerous compact prominent usually 

 forked or fascicled extending to and uniting with an intra- 

 marginal vein ; fertile fronds often equal in length to the 

 sterile ones simple and linear or bipinnatifid or bipinnate, 

 primary pinucfi as long as the sterile ones linear-lanceolate 

 acuminate, pinnules i-| of an inch long obtuse terete or 

 slightly compressed covered (apparently) all over to the very 

 apex with capsules. — Siv. Sijn. Fil.jyp. 14 and 200. Willd. Sp. 

 PL V. p. 120. Olfersia, Kze. Bot. Zeit. 1842. \.p. 312. Hook, 

 and Grev. Ic. Fil. /. 81 . Hook. Fil. Exot. t. 43. Polybotrya, 

 Klfs. Osmunda, Lhm. Sp. PL p. 1521. Dorcapteris, Pr. — 

 Var. /S ; fertile fronds pinnate. Olfersia Corcovadensis, 

 Raddi, Fil. Bras. p. 7- t. 14. Pr. Polybotrya, Spreng. P. 

 Raddiana, A'^//^. Acrostichum linearifolium, Pr. — Plum. FiL 

 t. 154. 



Hab. Tropical America, frequent.— Some of C. Wright's specimens from Cuba 

 present a remarkable form with sterile pinns deeply pectinato-pinnatifid, some 

 of the segments having sori at their apices. Another plant from New Granada 

 has the upper half of the sterile pinnae suddenly contracted and caudate, and 

 partially soriferous. 



** Fronds simple. — Aconiopteris. 



118. A. (Olfersia) yorgoneum, Klfs.; caudex a thick woody 

 knotted subdecumbent rhizome paleaceous at the summit, 

 stipites aggregated from the apex of the rootstock 3-5 inches 

 long twice as long of the fertile fronds, a little paleaceous at 

 the base, fronds coriaceous or subcoriaceous, sterile 6-12-14 

 inches long 2^-3 inches wide above the middle obovato- 

 spathulate rather suddenly acuminated long attenuated at 



