544 



LIFE-HISTORIES 



relatirely much greater stem-development, and in ha.ving the leaf- 

 members whorled, the sac-leares in cones, and the spores tvitli elaters. 



194. The club-mosses (Class LycopodinEe) are well typi- 

 fied by Lycopodium (Fig. 166) which is popularly regarded 

 as a kind of "moss" because of the general resenil)lance of 

 the leaves and stems, in form and proportionate develop- 

 ment, to the pseudo-leaves and pseudo-stems of many true 

 mosses. 



Fig. 372. — Club-aioss {Li/copodiuni sp., sec Fig. 166.) A, yametophyte {-'t), 

 sliowiiig archegonia (ar) and anthcridia (a7i). B, old gamctophyte (p) 

 nursing a young sporophyte, ^f. C, anthi'ridium {";-'-) almost ready 

 to discharge its spermatazoids. D, arehegonium, cut vertically to show 

 the egg-ccUs (o), the upper canal-cells dissolved into mucilage (/;c), 

 and the lower canal-cell (Ijc), -",-'-. (Treub.) 



The gainetophytc (Fig. 372) is liise.xual aud massive, as in the 

 aildcr-tongues, and mostly sapropli)'tic; and the emliryo resembles 

 that of a fern in havino; Isut a singles cotyledon. Its development is 

 essentially lil-:e that of the next type to be described. 



The .stem often forks but shows no secondary thickening. 

 The leaves are unbranched, and in some species are all much 

 alike, while in other cases tlu> sac-leaves are smaller than the 

 foliage h'aves, are crowded into cones, an<l serve chiefly as 

 protective scales for the sp(.)rangia. Each sac-leaf l)ears Init 

 a single spore-case on its upper surface near the base. There 

 are no elaters. 



