62 
illustrate structure and mode of reproduction. Fig. 12 is from 
a photograph of a species of Fucus, which is not uncommon 
from northern Massachusetts northward, growing usually on 
rocks near the low water mark. The genus Sargassum stands 
at the head of the rockweed family, both in number of species 
and in the highly specialized plant body. It is a species of this 
genus that is known to sailors as the gulf-weed or sargasso-weed : 
—a species that is most frequently found in a free floating con- 
dition. This forms wide floating mats covering more or less 
weed. (Fucus edentatus De 1a Pyl.) From Nova Scotia 
12, A Ro 
(hea one eighth natural size. ) 
densely thousands of square miles in the Atlantic Ocean between 
the West Indies and the African coast. The plant is brought 
north by the Gulf Stream and is occasionally washed ashore on 
Long Island. 
The exhibit of seaweeds culminates with the red algae, 4 
group in which the plants commonly offer some shade of red, 
pink, or purple. The display of the algae of this class is par- 
ticularly full, perhaps disproportionately so, eight of the cases 
