112 



DOMESTIC BOTANY. 



vulgatiim) and Moonwort {Botrychium lunaria). The former 

 is extensively collected by herb-gatherers, and being muci- 

 laginous is used in the preparation of salves ; its ancient 

 reputed virtues, as well as those of the moonwort, are merely 

 imaginary. A tropical species, Opliioglossum pendulum, grows 

 on trees, and hangs down like ribands, four to six feet in 

 length ; 0. palmatum, also growing in similar situations, has 

 its leathery fronds divided in lobes like the hand. 



FiLiCES (Ferns). 



Ferns are plants consisting of stem and leaves, the latter 

 called fronds, which are either simple and entire or 

 variously divided and spirally unfold, being traversed by 

 veins composed of indurated tissue. From different 

 parts of their underside or margin are produced clusters 

 or lines of spore-cases, called so7'i, the cases being mem- 

 branous, and furnished with a jointed elasticring (annulus), 

 or horny and ringless. The sori are either naked or 

 furnished with membranous coverings, called indusia. 

 The fronds vary in size from one inch to large decom- 

 pound fronds fifteen or more feet in length, some having 

 creeping thread-like stems, while others have tree-like 

 stems, fifty or more feet in height, bearing at the top a 

 crown of leaves. 



The Ringless Fern Family. 



, (Marattiace^.) 



Spore-cases destitute of a ring, either free or united, forming 

 valved cysts, each opening by a pore or sHt (Fig. 11, c). 

 These plants have often very large fronds, the different parts 

 of which vary in such a manner as to have led botanists to 

 describe a great number of species. Probably their number 

 does not exceed thirty, most of which are natives of the tropics, 

 one species extending to New Zealand and Norfolk Island. 



