u8 HOW TO KNOW THE FERNS 



bear at each joint a sheath ending in three long 

 pointed teeth. The stems of the Wood Horse- 

 tail are marked by about a dozen ridges. 



The Wood Horsetail is often abundant in 

 damp shady woods. 



Equisetum palustre. The specific name pal- 

 ustre means " belonging to the marshes." The 

 Marsh Horsetail. 



This plant has a very thick rhizome from 

 which arise the erect stems. The barren and the 

 fertile stems closely resemble each other, being 

 about a foot or more in height, with very rough 

 surfaces on which it is possible to count from 

 six to twelve very prominent ridges. The stems 

 are enclosed at intervals in loose sheaths, which 

 have the same number of teeth as the ridges on 

 the stem. It should be noted that the branches 

 from the various whorls show a marked tendency 

 to turn upwards. On certain of the stems the 

 fertile cone appears and the spores are ripened 

 about June, after which the process withers. 

 The plant as a whole remains green until 

 late in the autumn. Sometimes in the case 

 of large plants, cones have been known to 

 occur on the tips of the branches of the Marsh 

 Horsetail. 



The Marsh Horsetail is a very common species, 

 often growing in the greatest profusion by the 

 sides of pools. 



Equisetum limosum. In this case the specific 

 name is a Latin word which means " full of 

 mud " ; this being an allusion to the fact that 

 the plant favours swampy situations. The 

 Smooth Naked Horsetail. The plant is also 

 called the Water Horsetail. 



A distinctive feature of this plant is that it 

 has almost completely smooth stems, though a 

 close examination will indicate the presence of a 



