CERATOPTERIS. 235 



Sori continuous, arising from two principal longitudinal 

 but slightly anastomosing veins or receptacles on each side 

 between the costa and the margin. Capsules lax, scattered 

 on the receptacles, subglobose, sessile, obscurely reticulated ; 

 annulus very broad, nearly complete, or reduced to five or six 

 indistinct articulations, or quite obsolete. //«t'o/MC?'e membra- 

 naceous, continuous, formed of the reflexed margins of the 

 frond, which are broad, and meet at the back. Seeds or 

 spores few, very large, obtusely trigonal, each of the three 

 faces beautifully concentrically striated, filled with an olea- 

 ginous substance. — Tropical aquatic Yqxw, floating, or attached 

 to soil in shalloio waters, very peculiar in habit and mode of 

 growth, and extremely variable in form. Roots tnf ted. Fronds 

 membranous, subsucculent ivhen fresh, pellucido -punctate ivhen 

 dry. Sterile and fertile different, several from the same root, 

 proliferous in every part. Sterile subfoliaceous, simple or 

 more or less divided : young and less divided ones horizontal 

 and floating ; more advanced, bi-tripinnate and much dissected, 

 emerged, erect; veins all anastomosing. Fertile ones generally 

 taller than the sterile, bi-tripinnate, with linear, obtuse, some- 

 V)hat siliquose segments, everywhere soriferous. Stipites in 

 both, thick, inflated, with large air-cells. 



1. Ceratopteris thalictroides. 



Ceratopteris thalictroides, Brongn. I. c. Hook. Gen. Fit. I. c. 

 Wall. Cat. n. 83. Brackenr. Fil. U. St. Expl Eocped. p. 67. 

 Pteris thalictroides, Siv. Syn. Fil. p. 98. Willd. Sp. PL v. 

 p. .378. Acrostichum thalictroides, Linn. Sp. PI.]}. 1527- Fl. 

 Zeyl. n. 371. t. 4. Acrostichum siliquosum, Linn. Sp. PI. 

 p. 1527. Fl. Zeyl. n. 376. Amoen. Acad. i. p. 270. /. 3. 

 Teleozoma thalictroides, Br. in Frankl. Journ. I. c. p. 54. 

 Ceratopteris Gaudichaudii, Brongn. in Frey. Voy. Bot. \.p. 393. 

 /. 20 [small fertile fronds only). Ceratopteris Richardii, Ad. 

 Juss. Diet. Class. d'Hist. Nat. iii. p. 531. Pteris cornuta, 

 Beauv. Fl. d'Oware et de Ben. p. 63. t. 38. Le Prieur, Ann. 

 des Sc.Nat. x\x. p. 99. /. 3 [young proliferous fronds, capside, 

 and spores). Pt. succulenta, Roxb. in Cal. Journ. of Nat. Hist. 

 iv. p. 508. Ellobocarpus oleraceus, Kaidf. En. Fil. p. 148. 

 Belvisia siliquosa, Mirb. Parkeria pteridioides, Hook. Exot. 

 Fl. ^ 147 and 231. Huok. et Grev. Ic. Fil. t.97- Ceratopteris 

 Parkeri, /. Sm. Mctten. Parkeria Lockhartii, i^ooA'. e^ Grey. 

 /. c. under t. 97- Millefolium aquaticum, Rumph. Amb. vi. 

 p. 176. /. 74. /. 1. Planta siliquosa, Pluk. Aim. t. 15. / 3. 



