OTHER CRYPTOGAMS IN CULTIVATION. 155 



are such, that it may be an introduced species even 

 there. 



The Lycopodiacea are highest among Crypto- 

 gams. The order contains the genera Isoetes, 

 Psilotum, Tmesipteris, Lycopodium, Selaginella, 

 and Phylloglossum. Even a superficial examina- 

 tion of them will suggest resemblances to plants 

 of higher structure among the Phanerogams. 

 Some of the Lycopodiums remind us of a pine- 

 tree, and the fruit-spikes of many resemble pine- 

 cones. Humble as they now are, they can boast 

 of noble ancestors among the Lepidodendrons of 

 geologic antiquity, whose towering stems during 

 the Carboniferous Period reached a height of six- 

 ty feet, and which were plants closely connected 

 by the Sigillarias to the Conifers. We have in 

 America Psilotum, a plant which grows in Florida, 

 and resembles the beech-drops (Epiphegus Vir- 

 giniand) ; and Isoetes, which is an uninteresting 

 grass-like plant growing in shallow water, and hav- 

 ing its spores at the bases of the leaves. 



The species of the genus Lycopodium are diffi- 

 cult to establish in cultivation ; and so many 

 writers allude to this fact, that it must have been 

 proved by multiplied and fruitless experiments 

 everywhere among horticulturists. Of our common 

 species, L. dendroideum, complanatum, lucidulum, 

 and annotiimm are beautiful plants, and much in 

 demand for use as evergreens in all kinds of deco- 

 ration. 



