11 



SPEC] ES, 



Sub-class I. MELANOSPEBMILE. 

 Obdee 1. FUCACEJE. 



I. SARGASSUM. 



1. vulgare (77//? common Sargassum) ; stem filiform, smooth, 



alternately branched . Leaves linear-lanceolate or oblong-lan- 

 ceolate (very variable in breadth), serrated, strongly ribbed, 

 copiously glandular; air-vessels on compressed stalks about 

 their own Length, spherical, pointless; receptacles axillary, 

 dichotomous, tuberculosa, unarmed, A<j. &p. Ah), v. 1. p. 3. 

 (Atlas, PL I. Fig. 1.) 

 Fucus natans (in part), Turn, f. U114. 



Hah. Atlantic Ocean, abundant on the tropical and subtropical 

 tsts. Cast on the British coasts, drifted by oceanic cur- 

 rents from warmer latitudes. 

 One of the stray waifs of tropical climes, which are oc- 

 casionally broughi to our shores by the great north-eastern 

 cm-rent of the Atlantic, and which have do proper claim 

 to admission into our Flora. Though the present species 

 has bad a place in British works for nearly a century, I 

 have never seen a (so-called) British specimen, and have 

 made my figure from an American example. 



2. bacciferum (The berry-bt taring Sargassum) ; Btem cylindri- 



cal, slender, much branched, Hexuous • Leaves linear, ser- 

 rated, mostly without muciferous pores; air-vessels abundant, 

 spherical, <»n cylindrical stalks commonly mucronate, Ag, 

 Sp. Alg. >-. l. p, 6. (Atlas, PL I. Pig. 2.) 

 Fucus bacciferum, Turn. F, natans, Esper. F, Bar 



Hub. Tropical and subtropical ocean, throughout both hemi- 

 sphere-, always found floating on the Burface oi' the sea. 

 Occasionally oast on the British coasts, but not a native of 

 our waters. 



This plant, ilie well-known Sargasso or Gulf- weed, has 



