Clubmosses and their Relatives 

 CHAPTER VII 



CLUBMOSSES AND THEIR RELATIVES 



To young botanists it always comes as a great surprise 

 to learn that the lowly clubmosses are closely related 

 to ferns, to which outwardly they bear no resemblance 

 whatever. This feeling of surprise vanishes, when the 

 marked similarity in their life-histories is made clear. 

 Both may be traced back to a spore, which, on germinat- 

 ing, produces a prothallium, from which, later on, springs 

 the new plant. But in the case of some of the club- 

 mosses it may be well to note that the spores take 

 years to germinate, and that a further interval of years 

 elapses after the production of prothallia, before the 

 male and female organs are developed. 



Most of these prothallia, too, unlike those of ferns, are 

 produced under and not on the surface of the soil. In 

 all other respects ferns and clubmosses are very dis- 

 similar. Ferns possess, as a rule, large deeply divided 

 leaves, while clubmosses have short, entire leaves closely 

 arranged round the long, creeping, and forked stems. 

 In ferns the spore capsules are borne in clusters on the 

 backs or edges of the fronds, but in clubmosses they 

 appear singly, either at the bases of the ordinary leaves 

 or on special leaflike bracts clustered together on an 

 erect stalk to form the so-called "cone." The single 

 capsules, which are large compared with those of ferns, 

 64 



