304 



BOTANY 



Lycopodiineae, Psilotineae, Selaginellinese. 

 sporous, the latter heterosporous. 



The two first are homo- 



OBDEB I. LYCOPODIINEAE 



The Lycopodiineae include about one hundred species, all of which, 

 except the peculiar Phylloglossum Drummondii of Australia, belong 

 to the genus Lycopodium, which 

 includes the common " Club- 

 mosses," " Ground-pines," etc., of ^ ^ ^ 



B 



FIG. 269. A, Lycopodium clavatum, 

 gametophyte (x3). B, L. annotinum, 

 gametophyte with sporophytes, sp, at- 

 tached (X 3). C, gametophyte of 

 L. complanatum (X3). (All after 

 BRUCHMANN.) 



the northern forests. Some of 

 the tropical species, like L. phleg- 

 maria, are epiphytes. 



FIG. 270. A, Lycopodium clavatum. 

 B, sporophyll of L. obscurum. C, 

 section of the stem of L. obscurum. 



The Gametophyte 



Our knowledge of the gametophyte of Lycopodium is now quite complete. 

 There are a number of distinct types, which ought, perhaps, to lead to a sepa- 

 ration of the species into several genera. In some species e.g. L. inundatum, 

 L. cernuum the prothallium (Fig. 271) consists of an upright cylindrical body 

 terminating in a crown of green leaflike lobes, among which the sexual organs 

 are found. In the other species (Fig. 269) it is a subterranean, saprophytic 

 plant, like that in Botrychium. In L. phlegmaria, the saprophytic gametophyte 

 grows below the bark of decaying branches. Where the germination of the spores 

 has been studied, the spore first gives rise to a small cellular body, the primary 

 tubercle, from which the gametophyte develops as a branch. 



