1057 



Equisetum ^ fiina t He, Fries. 



and, when growing, somewhat 

 scabrous above. 



Barren stem with 30-45 joints, 

 and a longy lax, slender, branch- 

 less, blunt termination ; fertile 

 stem with 20-SO ^omis,/re(juentli/ 

 overtopped by the uppermost whorl 

 of branches. 



Primar}' sheaths (vaginae) darker 

 in colour than the stem, more 

 faintly but similarly striated, with 

 rigid, acuminate, purplish black 

 teeth, equalling the striae in num- 

 ber. 



Branches multangular, ribbed 

 like the stem, long and slender, 

 tapering upwards, almost invari- 

 ably longer than the internodes, 

 usually twice their length, occa- 

 sionally few in number and irre- 

 gularly disposed, but more fre- 

 quently numerous and arranged 

 in lax whorls, spreading at an 

 angle of about 45° with the stem, 

 ultimately somewhat pendulous. 



Secondary sheaths (vaginulae) 

 lax, the upper uniform in colour 

 with the branches, but with their 

 acute teeth tipped with purplish 

 black, the lowest with subobtuse 

 teeth, coloured throughout. 



Spike more or less stalked, slen- 

 der, resembling that of E. palus- 

 tre in size and shape, at first 

 roundish, afterwards ovate-lanceo- 

 late, without an apiculus.* 



Equiselum limosum, Fries. 

 smooth throughout. 



Barren stem with 30-40 joints, 

 and a comparatively rigid termi- 

 nation, narrowing gradually up- 

 wards ; fertile stem with 20-30 

 joints, never surmounted by its 

 branches. 



Primary sheaths (vaginae) darker 

 in colour than the stem, more 

 faintly but similarly striated, with 

 rigid, acuminate, purplish black 

 teeth, equalling the striae in num- 

 ber. 



Branches multangular, ribbed 

 like the stem, short and rigid, 

 nearly equal throughout, usually 

 nearly equalling the internodes in 

 length when matured, arranged in 

 regular erecto-patent (" arrect ") 

 whorls. 



Secondary sheaths (vaginulae) 

 lax, the teeth of the upper acute, 

 of the lowest subobtuse, all nearly 

 uniform in colour with the branch- 

 es, but faintly tipped with purplish 

 black. 



Spike nearly sessile, thick, gib- 

 bous, black, ovate, blunt. 



* For conveuience of comparison, I subjoin the notes of Fries, accompanying his 

 illustrative specimens in Herb. Norm. 1. c, kindly furnished to me by Mr. Babiug- 

 ton : — 



