312 CHARACTERS OF TRIBES AND GESEEA. 



/to?!c2s contracted, bipinnate, segments baccfeform, compactly 

 filled with sporang-ia, Tvhich rise from four to six puncti- 

 form receptacles, each furnished with a lateral, cucullate, 

 membraneous indusium. 



Type. Onoclea sensihiJis, Linn. 



lUust. Hook, and Bauer, Gen. Fil., t. 82 ; Moore, Ind. 

 Fil., p. 65 A. ; J. Sm., Ferns, Brit, and For., fig. 106 ; 

 Hook., Syn. Fil., t. 1, fig. 9. 



Obs. — This genus, as here restricted, consists of a solitary 

 species of peculiar habit and somewhat doubtful relation- 

 ship. In my Arrangement of 1841, and previously (1838), 

 in a note at tab. 82 of Hooker and Bauer's " Genera 

 Filicum," I stated that the membraneous scales found inter- 

 posed between the confluent sori were truly special laterally 

 attached indusia, and I therefore placed it in proximity 

 with Aspidium, thus removing it from the vicinity of Blecli- 

 nnm and Woodwardia, where it originally stood, but later 

 and more careful examination of the natural atfinities of 

 Ferns, has led me to place it again in the tribe Blechicce, 

 its nearest ally being the genus Lorinseria. 



In the " Species Filicum " the genus Strutliiopteris is 

 united with Onoclea, bat it is quite at variance with Onoclea 

 technically as well as in habit. 



Sp. 0. sensibilis, Linn, (v v.) 



A native of North America. 



179. — Stenochlj;xa, /. Sm. (1841). 

 Acroaiichum auct., Hooh. Sp. Fil. 

 Vernation uniserial, distant, sarmentum elongated, scan- 

 dent. Fronds 2 to 3 feet long, of two forms, the sterile 

 pinnate, the fertile contracted, pinnate or bipinnate ; pinnce 

 articulated with the rachis. Feins rising from an obscure 



