350 EQUISETACEvE. [Equisetum. 



upwards ; sterile stem slightly scabrous, with twelve to fourteen 

 furrows ; teeth of the sheath lanceolate-subulate ; branches 

 simple, erecto-patent ; fertile stem without branches, its sheaths 

 remote, loose. Br. Fl. ed. 3. p. 459. E. Fl. v. iv. p. 337. 

 E. Bot. t. 2020. 



Corn-fields and road sides, frequent. FL April ; afterwards the 

 sterile stems appear. 



* * Fertile stems at length throwing out whorled branches, or 

 bearing the fructifications at the same time with the whorled 

 branches. 



4. E. sylvaticum, Linn. Branched Wood Horse-tail. Sterile 

 and fertile stems with about twelve furrows ; branches com- 

 pound, whorled, deflexed ; sheaths lax, with about six or twelve 

 long membranaceous, obtuse teeth. Br. FL ed. 3. p. 459. E. 

 Fl. v. iv. p. 336. E. Bot. t 1874. 



Moist woods and hedge-banks, chiefly in mountainous situations. 

 Near Roundwood and other places in the County of Wicklow ; abund- 

 ant in the north. FL April, May. A very elegant species, twelve or 

 eighteen inches high. Sterile plants pyramidal in their catkin ; fer- 

 tile ones abrupt at the top, especially after the fructification has passed 

 away. 



5. E. limosum > Linn. Smooth naked Horse-tail. Stem 

 smooth, striated ; striae about 16 18 ; teeth of the sheaths 

 short, rigid, distinct; branches nearly erect, simple, often abor- 

 tive ; catkin terminal upon the stem. Br. Fl. ed. 3. p. 459. 

 E. FL v. iv. p. 339. E. Bot. t. 929. 



Watery places and ditches, frequent. FL June, July. Next in size 

 to E. fiuviatile : agreeing, too, somewhat in habit ; but with fewer 

 angles and teeth, and fewer branches in a whorl, and these latter often 

 short and imperfect, or wanting ; and differing, by the catkins being 

 upon stems that are similar to the barren ones. 



6. E. palustre, Linn. Marsh Horse-tail. Stem furrowed, 

 roughish, with seven or eight angles ; branches simple, gra- 

 dually shorter upwards (sometimes abortive), catkin terminal 

 on the stem. Br. Fl. ed. 3. p. 459. E. FL v. iv. p. 339. E. 

 Bot.t. 2021. 



p. E. palustre minus potystachion, Bauh. Prodr. 24. Dill, 

 in Raii Syn. 131. t. 5. f. 3. 



Boggy soils, frequent. & (<y. Smith}. Spikes terminating the 

 upper branches as well as the stem. FL June, July. 



* * * Stems simple, or irregularly branched; fructifications 



terminal. 



7. E. hyemale, Linn. Rough Horse tail. Stem throwing 

 up simple branches only from the base, scabrous, furrowed, 

 rough ; sheaths with about fourteen very small, obtuse, often deci- 



