Br. Greville on some new species of Sargassum. 275 



taculis axillaribus,racemosis,planis, lineari-cuneatis, acute et grosse 



denticulatis. 

 Wight in herb. no. 18. 

 Hab. in mari Indico, ubi detexit Wight. 



Root unknown. Plant of a bushy habit, about two feet long. 

 Stem cylindraceous, about as thick as a crow-quill, giving off 

 branches 6-8 inches long at intervals of less than an inch apart ; 

 these branches are clothed with a second series 1-2 inches in 

 length, on which the short fruit-bearing ramuli are thickly set. 

 Leaves cartilaginous, fully an inch long, shortly petiolate, oblong- 

 lanceolate, very irregularly repando-dentate, obtuse, the nerve 

 extending almost to the apex, punctate, the pore visible to the 

 naked eye. Vesicles between oval and spherical, about the size 

 of hemp-seed, very numerous, intermixed with the receptacles, 

 on broad foliaceous stalks, often winged and apiculate, frequently 

 developed in the leaves themselves. Receptacles axillary, vary- 

 ing in length from little more than 1, to 2 or even 3 lines, race- 

 mose, more or less linear, flat, so largely and sharply toothed as 

 to be sometimes almost pinnatifid. Colour a rich dark reddish 

 brown. Substance cartilaginous. 



In habit this species is allied to S. vulgare, but differs entirely 

 in the fructification and other leading characters. The sportive 

 disposition of the vesicle is very remarkable, showing every trans- 

 ition from the leaf to that organ. On one occasion I observed 

 two vesicles imbedded in the same leaf, as represented at fig. 3. 

 The leaves occasionally assume a broadly linear character, and if 

 I am correct in referring one imperfect specimen in my posses- 

 sion to this species, they become sometimes more elongated and 

 at the same time less toothed. 



Campbellian^e. 



5. Sargassum Campbellianum (nob.) ; caule filiformi ; foliis membra- 

 naceis, linearibus, dentato-serratis, obtusis, uninerviis ; vesiculis 

 paucis, sphaericis, breviter petiolatis ; receptaculis racemosis, ellip- 

 tico-cylindraceis ad apicem denticulatis. 



Hab. in mari Indico. Specimina communicavit J. Campbell. 



Root unknown. Entire plant probably three feet long or more, 

 of a very slender and graceful habit. Stem filiform, cylindrical, 

 elongated, in my imperfect specimens nearly two feet in length, 

 producing horizontal branches at remote intervals 6-9 inches 

 long or more, which bear numerous ramuli 1-3 inches long; 

 these ramuli are clothed with leaves and receptacles at intervals 

 of often not more than the eighth of an inch. Leaves petiolate 

 (those on the primary branches l| inch, those on the ramuli 

 less than an inch long), linear or nearly linear-lanceolate, irre- 

 gularly dentato-serrate, either acute or quite obtuse at the apex, 



19* 



