CLUB-MOSSES AND THEIR ALLIES. 127 



XII. CLUB-MOSSES AND THEIR ALLIES. 

 L.YCOPODINEJE. 



MATERIAL REQUIRED. 



Fresh specimens of Selaginella from the conservatory. A number of 

 species are common in cultivation, and any of them may be used. 



Club-moss, Lycopodium clavatum, L., with spore-bearing spikes. Simi- 

 lar specimens of other species of the same genus, e.g. L. lucidu- 

 lum, Michx., L. complanatum, L., etc. 



Any other vascular cryptogams that are procurable, as Marsilia or 

 Isoetes. 



SELAGINELLA. S. stolonifera, denticulata, etc. 

 General Characters. 



I. Record your observations of the plant as a whole. 

 Where did it grow, and under what conditions ? Point out 

 any peculiarities of form, texture, or habit, by which it 

 would readily be distinguished from ferns. 



II. Examine carefully the mode of branching. Draw a 

 diagram to represent it. Is it dichotomous or monopodial' n 

 The plant is said to be bilateral and dorsi-ventral ; show 

 how this is true. How do you distinguish between the 

 dorsal and ventral aspect of the plant ? 2 



III. Describe the form and arrangement of the leaves. 

 Are they all alike ? How many rows are there ? 



IV. On well-developed specimens, slender, root-like 

 organs, rhizophores, are to be found. Notice where these 



1 Cf. Bower and Vines, Practical Botany, I, p. 162. 



2 Cf. Strasburger, Practical Botany, p. 296. 



