SECT. I. CONSERVATIVE ORGANS. 



generally of a strap-shaped figure, scattered pro- 

 miscuously over the stem and branch, and often so 

 closely crowded together as to overlap one another 

 like the tiles of a house. 



The Frond. The most general feature characteriz- Defini- 

 ing the growth and habits of Ferns is that of the frond, 

 being an incorporation of the leaf, branch, and 

 stipe, as in the genus Scolopendrium. In the early 

 stage of its growth the apex is in most genera rolled 

 inwards like a scroll, forming a number of convoluted 

 curves, which are unfolded as the plant expands, the 

 figure of the frond being ultimately lanceolate, as in 

 Aspidium Lonchitis ; or deltoid, as in Asplenium 

 Adiantum nigrum ; or oval, as in Ophioglossum 

 vulgatum, and its position erect, as in Asplenium 

 septentrionale ; or spreading, as in Aspidium dila- 

 iatum. It is also simple, that is without divisions, as Modifica- 

 in Ophioglossum, or wing-cleft, as in Polypodium tl( 

 vulgare ; or winged, that is either simply, as in 

 Osmunda Lunar ia, or doubly, as in Osmunda 

 regalis, the wings being also either opposite, as in 

 Asplenium Tr-ichomanes, or alternate, as in Aspi- 

 dium Filix-mas, and the portion of the frond to 

 which they are attached being, as in the case of 

 the fructification of the Grasses, denominated the 

 Rachis. 



Its magnitude, at least as regarding British 



species, is from a span in length, as in Cyathea 



fragilis, to three or four feet, as in Pteris aquitina ; 



