Mindeskrift tor J. Steenstrup. XXXII. 



This species is very common along tiie shores of the islands and occurs in exposed 

 or sheltered piaces. In exposed localities, where the sea constantly splashes the rocks 

 Sargassum valgåre is able to thrive above the surface; in the more sheltered piaces it 

 occurs close to the surface, or a little below. 



Sargassum vulgare is the dominant species in the Sargassum-Ne§,eisXion forming 

 with Turbinaria trialata a vegetation of large, brown algæ corresponding with the 

 Fucaceæ-Associ[ation in northern seas. 



Geogr. Distrib. Tliis species is said ' to occur 

 at nearly all subtropical and tropical shores of the At- 

 lantic Ocean: America and the West Indies, Africa, 

 Spain etc. 



2. Sargassum IcndigfTum (L.) Kiitz. 



KtiTziNG, Species Algarum, p. 612. 



— , Tabulæ Phycologicæ, vol. XI, tab. 19, fig. II. 

 J. Agardh, Species Sargassorum Austral., p. 110. 

 Fucus lendigerus L., Species plant., p. 1628. 

 Turner, Fuci, p. 107, tab. 48. 



The specimens which I have referred to this 

 species possess leaves with a distinct midrib and 

 small, most often scattered cryptostomata; these 

 are, sometimes, arranged more or less regularly 

 in a single series on both sides of the midrib. 



The basal leaves are more or less dentate; 

 the superior have a somewhat sinuate to entire 

 margin. 



The leaves are linear-elliptic 4 — 5 mm. broad, 

 and until 3 cm. long, with a short stalk or ses- 

 sile. The vesicles are scarce, often quite absent; 

 when present, according to my observations, they 

 occur only at the upper end of the branch; they 

 reach the size of a small pea, and are often 

 sonii'what oval, now and then provided with a small, leaf-like prolongation at theirapex. 

 The receptacles are mostly aggregated at the upper end of the branches; they are 

 cylindric and irregularly branched. 



This species appears to be closely related to Sargassum vulgare, representing prob- 

 ably a mere variety of it. 



St. Thomas: Store Nordside Bugt, growing in a rather exposed place. 

 Geogr. Distrib: West Indies, Bermuda, Tenerilla etc. 



Fig. 1. Sargassum vulgare C. Ag. Part of a 

 plant with receptacles and vesicles. ( A litle 

 over natural size, about Vo magnified). 



