Rhynchospora alba and li. fusca. 675 



antennae are 3 in number, the central one larger and longer 

 than the others. The description of the proboscis is incor- 

 rect ; for the margin is fringed with a double series of papil- 

 lary tentacula, not with "a series of corneous serrated plates." 

 4. Lycbrh margaritdcea. f(VII. 231.) — I have since as- 

 certained that this is not the L. margaritacea, so that the 

 references to Lamarck, Leach, and Stark, among the syno- 

 nymes, ought to be erased. The other references will, I be- 

 lieve, be found to be correctly applied. The figure is far 

 from being a good one ; but I hope soon to give a monograph 

 of this genus with more correct illustrations. 



Art. IV. On the Specific Distinction of Rhynchospora dlba and 

 Rhynchospora fusca. By W. A. Leighton, Esq., B.A. 



During several unsuccessful attempts to discover that rare 

 British plant Rhynchospora fusca, which is stated, on the au- 

 thority of an excellent and accurate botanist, the late Rev. 

 Edward Williams, to grow at Bomere Pool, near this town, 

 I have repeatedly had occasion to refer to our floras for de- 

 scriptions of both the species of Rhynchospora indigenous to 

 Britain, and as repeatedly to lament the indefiniteness of the 

 characters by which they are there distinguished. This con- 

 stant reference has been rendered necessary, in consequence of 

 my gathering at Bomere Pool, and also on Twyford Vownog, 

 near Westfelton, Shropshire, a plant growing in great abun- 

 dance, intermixed with the usual state of Rhynchospora alba, 

 which, so far as regards the comparative length of the spikelets 

 and the outer bracteas, and the somewhat oval, appearance of 

 the heads, evidently agrees with Rhynchospora fusca as de- 

 scribed in Hooker's British Flora, 3ded. p. 27* This uncer- 

 tainty naturally induced a desire to investigate with accuracy 

 the real specific distinctions of the two species; which I have at 

 length been enabled most successfully to accomplish, through 

 the kindness of my friend C. C. Babington, Esq., furnishing me 

 with dried specimens of Rhynch6spora fusca, gathered by him 

 at Oughterard, in the west of Ireland, during the last month. 



The result of this enquiry has arranged the doubtful state 

 of R. alba, above alluded to, in its proper place, as a variety 

 only of that species, and has also supplied some excellent and 

 very decisive marks of specific distinction, which I have em- 

 bodied in the following detailed descriptions of the two 

 species, and which, it is confidently hoped, will tend to remove 



3b 2 



