44 
EQUISETACE^. 
This species appears to be generally distributed : it occurs in 
all the county lists of ferns which I have received, and is rarely 
mentioned either as local or uncommon. In Ireland I found it 
particularly abundant, especially in the north : in the vicinity 
of the Giant’s Causeway I observed several large patches of 
ground densely covered with it. I have not seen it in such pro- 
fusion elsewhere. 
The old figures usually quoted as representing this plant must 
be received wfith 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 pre- 
sent species. Ray’s figurej represents a variety hereafter to be 
noticed. The modern figures of course more nearly resemble 
the plant : that in English Botany is very good. 
Gerarde’s description appears to comprehend more than one 
species, — “the great thicke jointed stalk” describing Eq.Jlu- 
viatile of Linneus, while the roughness and hardness seem inap- 
plicable 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 wa- 
ter, hath a very long root according 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 fashion. The whole 
plant is also tough hard and fit to shave and rub woodden things 
as the other.” 
It is not however only in these ante-Linnean works that the 
synonymy of this and the following species is involved in obscu- 
rity. Our modern authors, I regret to say, have hitherto done 
but little towards the elucidation of the nomenclature. In the 
hope of making the subject somewhat more clear, I have 
introduced, in the Appendix, § some observations on the speci- 
mens in the Linnean herbarium. Unfortunately, the Linnean 
characters are frequently obscure, owing to the constant en- 
deavour of their celebrated author to make them as concise 
* Ger. Em. 1113. f Lobel, 795. \ Syn. tab. v. fig. 3. 
§ See Appendix C. 
