CL. XXIY.] CRYPTOGAMIA EQUISETACEJS. 395 



grows near the summit of high mountains : common. Eng. Bot. 

 vol. iv. pi. 233. Eng, Fl. vol. iv. p, 333. 1505. 



5. L. annotinum. Interrupted Club-moss. Stems decumbent at 

 the base ; branches ascending, forked ; leaves in five rows, narrow 

 lance-shaped, acute, minutely serrate ; spikes cylindrical, solitary, 



sessile. From six to eight inches high. Perennial : bears fruit 



in July and August : grows on the mountains of Scotland and 

 Wales. Eng, Bot. vol. xxiv. pi. 1727. Eng, Fl, vol. iv. p. 334. 1506. 



6. L. alpinum. Savin-leaved Club-moss. Stems prostrate ; branches 

 in tufts, erect, forked, level- topped ; leaves acute, keeled, imbri- 

 cated in four rows ; spikes terminal, solitary, sessile, cylindrical, 



their leaves broadly lance-shaped, flat. Perennial : bears fruit 



in August : grows on the higher mountains of Scotland, Wales, 

 and the north of England : frequent. Eng. Bot. vol. iv. pi. 234. 

 Eng. FL vol. iv. p. 335. 1507. 



Order III. EQUISETACE^E. Fructification terminal, spiked, 

 consisting of many peltate, angular, stalked scales, which 

 bear at the back from four to seven oblong membranous cells, 

 each containing numerous minute seeds, encompassed by four 

 filaments, terminating in four flat anthers, 



1. EQUISETUM. HORSE-TAIL. 



Spike oblong, of many peltate, stalked scales, arranged on a 

 common stalk. Scales angular, bearing at the back from four 

 to seven oblong membranous cells, parallel to each other, finally 

 bursting into two equal valves. Seeds globular, very minute, 

 having four spiral filaments attached to their base, which termi- 

 nate each in a flat appendage or anther, producing pollen. 

 Name from equus, a horse, and seta, a hair. 476. 



1 . E, arvense. Corn Horse-tail. Sterile stems decumbent at the 

 base, with undivided, angular, roughish, ascending branches; fer- 

 tile stems erect, destitute of branches, their sheaths distant, deeply 



toothed. Fertile stems about eight inches high, appearing before 



the sterile ones, which are from one to two feet high. Perennial : 

 flowers in March and April : grows in fields and meadows : com- 

 mon, Eng. Sot. vol. xxix. pi. 2020. Eng. Fl. vol. iv. p. 337. 1508. 



2. E. Drummondii. Blunt-topped Horse-tail. Sterile stems stri- 

 ate, rough with prominent points, with undivided, angular, rough 

 branches ; fertile stems erect, destitute of branches, their sheaths 



approximated, with narrow, tapering teeth. Perennial : flowers 



in April. Found by Mr. T. Drummond, in Forfarshire. Hooker. 

 Brit. Fl. p. 451. 1509. 



3. E.fluvidtile. Great Water Horse-tail. Sterile stems with very 

 numerous undivided, angular, roughish branches : fertile stems 



unbranched, their sheaths crowded, deeply toothed. Fertile 



stems from one to two ; sterile ones from two to four feet high. 

 Perennial : flowers in April : grows at the edges of rivers and lakes : 

 frequent. Eng. Bot. vol. xxix. pi. 2022. Eng. Fl. vol. iv. p. 337. 1510. 



4. E.sylvdticum, Wood Horse~tail f Sterile and fertile stems 



