154 ENGLISH BOTANY. 



and without branches ; but after the spike is matured becoming 

 firmer, white or greenish, and emitting whorls of branches similar to 

 those of the sterile spikes, but shorter. Spike obtuse, at first greenish- 

 white, afterwards fawn-colour. 



SPECIES III.— E QUISETUM PRATENSE. Ehrh. 



Plate 1890. 



Babenh. Crypt. Vase. Europ. Exsicc. Nos. 41, 42. 



E. umbrosum, Meyer, in Willd. Sp. PI. Vol. V. p. 3. Koch, Syn. Fl. Germ, et Helv. 



ed. ii. p. 965. Hook. & Am. Brit. Fl. ed. viii. p. 599. Newm. Brit. Ferns, ed. ii. 



p. 63. 

 E. Ehrharti, Meyer, Chlor. Hanov. p. 666. 

 E. amphibolium, Betz, Fl. Scand. supp. 2, p. 602 (teste Koch). 

 E. Drummondii, Hook. E. B. S. No. 2777. 

 E. sylvaticum, (3. minus, Wahlenb. Fl. Suec. p. 689, nup. 



Stems of two kinds, perishing in autumn. Sterile stem slender, 

 with 8 to 20 furrows, rather rough, green. Sheaths shortly funnel- 

 shaped, pale green, sometimes with a pitchy-brown ring at the apex ; 

 teeth 6 to 19, usually free, rarely some of them united in pairs or 

 threes, very narrowly triangular, hyaline with the exception of 

 a brown central firm rib, which is generally excurrent in a small 

 mucro, but sometimes does not reach the apex. Branches numerous, 

 usually 3-quetrous, with the ridges not grooved, and separated by 

 very deep furrows, solid, unbranched or rarely with a few branchlets, 

 their lowest internode shorter than the teeth of the stem-sheath below 

 which it is produced in the lower whorls, but equalling or exceeding 

 them in the upper whorls ; sheath enclosing the base of the first 

 internode of the branch brown, mostly wholly scarious towards the 

 apex, furnished with short rounded lobes ; sheaths at the apex of the 

 first and succeeding internodes of the branches, terminated by deltoid 

 blunt teeth. Fertile stem rather short, rather stout, at first slightly 

 succulent and reddish-white or very pale fawn-colour, ultimately 

 firm and green, slightly scabrous. Sheaths approximate, the lower 

 ones tubular-funnel-shaped and the upper funnel-shaped, sulcate, white 

 with a dark reddish-brown ring at the apex ; teeth 8 to 20, subulate, 

 almost wholly scarious, some of them occasionally united into groups 

 of 2 or 3, pale brown, with hyaline margins and a brown central 

 firm rib as in the sheaths of the sterile stem. Branches absent until 

 the fertile stem has attained nearly its full height, when they begin 

 to appear ; they are similar to those of the barren stem, but always 



