112 WAYSIDE AND WOODLAND FERNS. 



being surmounted by the egg-shaped cone, which is an inch 

 long, or nearly so. But occasionally the fertile stem comes 

 up without branches or with very short ones and develops 

 them later. The cones are ripe in April or May. 



A cross section of the stem shows a central cavity occupying 

 about one-third of the diameter, and with a scalloped outline. 

 Between this and the exterior wall is a ring of small 

 circular tubes, and alternating with these, but much nearer the 

 circumference, are a dozen larger half-egg-shaped spaces. 



The Wood Horsetail is rather a local species, but it ranges 

 from Shetland in the North to Devonshire and Kent in the 

 South. It is also found in Ireland. It appears to be the 

 most aspiring of our native species, for in the Highlands it 

 has been found at an elevation of 2700 feet. Its world- 

 distribution embraces Europe, Northern Asia, and North 

 America. 



The name Wood Horsetail is a book-name, for among the 

 folk it had passed merely with the other species under the 

 name of Horsetail or its local substitute. In some localities 

 it shares the name of Bottle-brush with the Field Horsetail. 

 Its Latin name is an adjective with precisely the same 

 significance as the English. 



Marsh Horsetail (Equisetum palustre). 



As its name implies, the Marsh Horsetail is a plant of swampy 

 grounds where rushes and mint and marsh marigold are its 

 companions. It is very variable in height, being anything from 

 six inches to two and a half feet in length, and though all 

 its stems, barren and fertile, are branched, there is a good deal 

 of irregularity in the branching and the degree of symmetry. 

 The grooves vary from five on the branches to twelve on the 

 stems : the latter have usually eight or nine. Though these 

 grooves are fairly deep they are also wide, and the alternating 



