428 Bibliographical Notices. 



f erred a new name upon the Irish species in compliment to Mr. Mackay, 

 the distinguished investigator of Irish botany, whom he had been led 

 to consider as its original discoverer ; it now however appears that it 

 was detected by the late Mr. Templeton long previously to its at- 

 tracting the notice of Messrs. Whitla and Mackay, and ought there- 

 fore, according to the rules for correct nomenclature, to be called 

 Mackaiana in place of Mackaii. It should however be observed that 

 Vaucher, although quoting Willdenow's E. elongatum as a probable 

 synonym of E. ramosissimum (Desf.), in which doubtless he is cor- 

 rect as far as the European localities are concerned, describes and 

 figures another species as E. elongatum (Willd.), to which he refers 

 the extra-European stations recorded by that botanist. This latter 

 plant very closely resembles E. Mackaii, and is perhaps what Sir W. 

 J. Hooker had in view when conferring the name of E. elongatum 

 upon the Irish specimens ; it is however quite distinct, as may be seen 

 by comparing Vaucher's description and figure with our plant. We 

 suspect that several species will ultimately be found to be included 

 under the name of E. variegatum, although sufficient data have not 

 as yet been obtained to allow of their separation upon paper. The 

 upright aquatic plant which has now been observed in many places 

 presents a very different appearance from the prostrate inhabitant of 

 loose and dry sands, and Mr. Moore has found them to continue 

 distinct in that respect, even when cultivated in a precisely similar 

 manner. It would appear that the name of variegatum belongs by 

 right to the plant of freshwater marshes, having been first employed 

 for a described plant by Weber and Mohr in 1807. If our sea-shore 

 plant, the E. variegatum of Smith, should prove distinct, the excellent 

 name of arenarium is already provided for it. There is still another 

 plant which may ultimately be separated from this species which was 

 found by Mr. W. Wilson in the lake at Mucruss near Killarney ; 

 this is upright, tall and stout, has a much smoother stem, and ap- 

 parently a differently shaped internal hollow. We have not seen it, 

 but should it prove distinct from the true E. variegatum of fresh water, 

 it will justly claim the appellation of E. Wilsoni conferred upon it 

 by Mr. Newman. 



Concerning the specific distinctness of the remaining species of 

 Equisetum there appears to be no difference of opinion ; not so upon 

 their names. The E. limosum of English authors is called fluviatile 

 by Newman, considering the limosum and fluviatile of Linnaeus as 

 only varieties of the same species, and in this he is borne out by the 

 Linnrean herbarium. Indeed we have no doubt that the E. limosum 

 (Sm.) is the original E. fluviatile (Linn.), but it seems equally cer- 

 tain that Linnseus afterwards included E. Telmateia (Ehrh.) under 

 that name, for he says (Mant. ii. 504) of E. fluviatile, " caules flo- 

 riferi a sterilibus distincti, ut E. arvensis, Hall." We ought not to 

 wonder that Sir J. E. Smith was misled by the adoption by Linnseus 

 of Haller's observation as applicable to his species, when we consider 

 how little the Linncean specific character affords upon which to found 

 an opinion, and that the specimens in his herbarium might well have 

 been misnamed. We now find that the specimens named E. fluviatile 



