OPHIOGLOSSACEiE. 



13 



OPHIOGLOSSACEJZ. 



Acrogens, with the stem erect or pendulous, with a cavity in 

 the middle instead of pith ; below, the stalks of the leaves and 

 the spike become blended together. Leaves with netted veins, 

 sometimes forked. Spore- (seed) cases collected into a spike, 

 two-valved, without any trace of an elastic ring. Spores re- 

 sembling fine powder. — Natives of the Tropics and temperate 

 latitudes. 



OPHIOGLOSSUM. (Adders-tongue.) 



Gen. Char. {Cryptogamia Filices.) Thecse naked, forming a 

 jointed spike of two rows, opening at the sides ; frond undivided. 



% The Greek for serpent and tongue gives the name to this 

 genus of ferns, from the form of the leaves. 0, vulgatum 

 is our w r ell-known Adders-tongue Fern, and several species 

 have been introduced into the greenhouse, as 0. gramineum 

 and costatum, from Australia ; bulbosum, from America, and 

 Lndtanicum, from Portugal, are even hardy enough to be 

 grown in the garden. 



BOTRYCHIUM. (Moonwout.) 



Gen. Char. (Cryptogamia Filices.) Thecse naked, globose, dis- 

 tinct, attached to a compound spike, opening nearly at the side. 



