504 Dr. Greville on soyne new species of Sargassum. 



to publish them in a modified form through the medium of the 

 Botanical Society. It is quite possible that during such an in- 

 terval of time the author of the ' Genera et Species Algarum ' 

 may have received from other travellers some of the species dis- 

 covered by Dr. Wight, in which case there will inevitably be a 

 collision of names ; and although my manuscript has been 

 lying by me for a long period, M. Agardh will have the unques- 

 tionable right which priority of publication confers. Where, 

 however, we may have unfortunately described under different 

 names the same plant, I may be allowed to hope that the figures 

 which I have given will assist in removing the confusion. 



19. Sargassum gracile (nob.); caule teretiusculo, filiformi ; foliis 

 linearibus, utrinque attenuatis, remote subdenticulatis, uninervi- 

 bus; vesiculis parvis, subsphsericis, muticis, petiolatis, petiolis 

 planis, dilatatis ; receptaculis ramosis, axillaribus, Hneari cuneatis, 

 ad apicem compressis, acute et grosse dentatis. 



Hub. in marl Peninsulee Indise Orientalis ; Wight. 



Root I have not seen. Plant, as far as I can judge from the 

 mutilated specimens before me, 2 or 3 feet in length or more. Stem 

 cylindraceous, filiform, giving off numerous spreading branches 

 at intervals of about one inch, and which are 6 inches to a foot 

 or more long. These branches are clothed with others several 

 inches in length, produced at shorter intervals, on which are 

 situated the fruit- bearing ramuli. Leaves an inch long or more, 

 about a line broad, linear, acuminate, almost entire, or remotely 

 denticulate, furnished with a nerve and pores, and attenixated 

 below into a very slender petiole. Vesicles about a line in dia- 

 meter, subspherical, sometimes slightly pyriform, destitute of 

 apiculus, supported on fiat, foliaceous, dilated stalks, 1-1^ line 

 in length, and produced from the raceme of fructification. Re- 

 ceptacles axillary, and occasionally also terminal, 1-2 lines long, 

 linear-cuneate, cylindraceous and unarmed below, compressed 

 and dilated above, and furnished at the margin and apex with 

 large, sharp, often curved teeth. The receptacles form a spa- 

 ringly divided raceme, one of the lower branches of which often 

 terminates in a vesicle. Occasionally a receptacle becomes tri- 

 quetrous in the upper part, in which case every angle is toothed : 

 sometimes receptacles appear to be proliferous, suggesting the 

 idea of a microscopic Cactus ; at others they are long and slender 

 to the apex which suddenly expands into a broad mass or crown 

 of foliaceous teeth. Colour reddish brown. Substance slightly 

 cartilaginous. 



The habit of the entire plant is lax and slender. 



20. Sargassum leptophyllum (nob.) ; caule brevi, tereti, tuberculato ; 

 ramis primariis compressis ; foliis integerrimis, angustissime line- 



