530 



This species appears to be generally distributed : it occurs in all 

 the county lists of ferns which T have received, and is rarely mention- 

 ed either as local or uncommon. In Ireland I found it particularly 

 abundant, especially in the north : in the vicinity of the Giant's Cause- 

 way I observed several large patches of ground densely covered with 

 it. I have not seen it in such profusion elsewhere. 



The old figures usually quoted as representing this plant must be 

 received with considerable doubt. Those of Gerarde* and Lobel,t 

 evidently printed from the same block, represent a plant growing in 

 the water, and having one erect and unbranched stem, and another 

 branched, and somewhat resembling the present species. Ray's 

 figure t represents a variety hereafter to be noticed. The modem fi- 

 gures of course more nearly resemble the plant. 



Gerarde's description appears to comprehend more than one spe- 

 cies. " The great thicke jointed stalk " describing Eq. limosum of 

 Smith, while the roughness and hardness seem inapplicable to that 

 species. I subjoin the passage as it stands in the herbal. "Water 

 Horse-taile, that growes by the brinks of riuers and running streams, 

 and often in the middest of the water, hath a very long root accord- 

 ing to the depth of the water, grosse thicke and jointed, with some 

 threds anexed thereto : from which riseth vp a great thicke jointed 

 stalk, whereon grow long rough rushy leaues pyramide or steeple fa- 

 shion. The whole plant is also rough hard and fit to shave and rub 

 woodden things as the other." 



It is not however only in these ante-Linnean works that the syno- 

 nymy of this and the following species is involved in obscurity. Our 

 modem authors, I regret to say, have hitherto done but little towards 

 the elucidation of the nomenclature. In the hope of making the sub- 

 ject somewhat more clear, I have introduced some observations on the 

 specimens in the Linnean herbarium. Unfortunately, the Linnean 

 characters are frequently obscure, owing to the constant endeavour 

 of their celebrated author to make them as concise as possible : in such 

 case a reference to the specimen becomes indispensable. It is, I be- 

 lieve, generally known, that the Linnean herbarium was purchased by 

 Sir J. E. Smith, and subsequently by the Linnean Society of London, 

 in whose possession it now remains. The specimens are fixed on 

 half sheets of foolscap paper ; they are named by Linneus himself, in 

 his own handwriting, and have also the comments of Sir J. E. Smith 



*Ger. Em. 1113. f Lob el, 795. + Synopsis, tab. v. fig. 3. 



