EQUISETACEJE. 151 



in England. Rare in Scotland, extending to Edinburgh on the east 

 .side and Skye on the west ; reported also from Fife and Forfar, but 

 these counties require confirmation. Not unfrequent, and generally 

 distributed in Ireland. 



England, Scotland, Ireland. Perennial. Spring. 



Rootstock creeping, about the thickness of a goose-quill, solid, 

 brownish-black, pubescent. Sterile stems erect, very variable in size, 

 but usually attaining to 2 or 3 feet, and not unfrequently even 

 4 or 5 ; and Mr. Sidebotham, in the ' Phytologist,' 1843, p. 649, says 

 that " in a wood below Arden Hall, Cheshire, it flourishes in a swamp 

 to the height of 6 or 7 feet." The stem is from the thickness of a 

 swan-quill to that of a man's finger, with very numerous sheaths, all 

 of which, except about 6 of the lowest, have whorls of branches at 

 their base. The lowest whorls are about lj inch apart or more, 

 closer together above, and quite approximate at the apex of the stem, 

 where the branches rapidly diminish in size. The colour is pale 

 bright-green, and the general form of the plant is cylindrical, 

 tapering towards the lower part, and blunt at the top. Fertile stems 

 4 inches to 1 foot high, about the thickness of a man's little finger, 

 tapering downwards at the base, with 7 to 18 sheaths, which are 

 placed so closely together that the lower part of the stem, and some- 

 times the whole stem, is concealed. I have, however, one specimen 

 from St. Mary's Church, Devon, in which the upper internodes are 

 2i| inches long, while the sheath itself is only 1^ inch. Spike li to 

 3 inches long, ultimately pale brown. 



The form of fertile stem (var. serotinum, A. Braun), which 

 resembles the barren one, is not a variety, but is due to certain 

 conditions of growth, and is not always developed from the same 

 plant. I have collected it myself at Haselmere, Surrey, and on the 

 debris of the under-cliff below Fairlight Grlen, Hastings, where 

 I observed many examples of it in 1862 ; I have seen it also on the 

 cliffs east of Southend, Essex, and the under-cliff at Folkestone. The 

 Haselmere and Fairlight Glen specimens are 18 inches or 2 feet high, 

 terminated by a spike of 1 or 2 inches ; the rest of the stem is quite 

 like the ordinary sterile plant, except that the sheaths are widened 

 upwards, though not so much as in the sterile plant : but the 

 Folkestone and Southend specimens are 4 to 6 inches high, with 

 spikes ^ to 1 inch long, have the sheaths close together, much widened 

 upwards, and so bear a much greater resemblance to the ordinary 

 fertile stem, except in being furnished with branches. 



If the rootstock be dug up at the time the sterile stem has reached 

 its full size, the buds of the fertile spikes may be observed near its 

 base, 1^ to 2 inches long, looking like small fir-cones from the over- 

 lapping of the teeth of the sheaths. These are developed in the 

 succeeding spring, about March, and disappear by May, at which time 



