296 THE SEA-WEEDS AT HOME AND ABROAD. 
alge, or sea-weeds, too. How insignificant appear our kelp- 
weeds in comparison with the Lessonia of the Antarctic Zone, 
trees with forking and branching trunks covered with crim- 
son brown, sinuated edged, and jagged-toothed leaves, or with 
blackish opaque foliage and twisted flexuous trunks, growing 
like submarine forests; or with the Nereocystis of the Aleu- 
tian islands, whose stem, never thicker than a packthread, ex- 
tends to the length of forty fathoms or more, and expands at 
the summit into an inflated cylinder from which issues a leaf, 
which gradually grows wider near its top; not singly, not 
here and there a plant but areas of great extent covered with 
innumerable plants; or with the Macrocystis whose slender 
stem and numerous leaves are buoyed up by their expanded 
and swollen base, the stem so long that fifteen hundred feet 
has been reported by observers as within the limits of belief. 
These several kinds of expanded fronds are employed as 
utensils among savage people, while the trunks of many of 
these gigantic alg: drifting on desert shores have been mis- 
taken and gathered for fuel, supposed to be actual wood. 
The structural arrangement of the cellular tissue on a 
number of the Melanosperms, giving to their fronds a pecu- 
liarly netted appearance when viewed through a magnifying 
glass, suggests a natural order, called Dictyotide, which sig- 
nifies like a net. Externally there is quite a variety among 
these sea-weeds, and of them we may search for Punctaria 
in two species, both parasitic on other and larger sea-weeds 
about Boston Harbor, or even Asperococcus with an inflated 
frond, while the others delight in a flattened one. The seeds 
may be found in the minute dot-like clusters scattered over 
the surface of the plants. To this order belong the curious 
Padina pavonia and its allied Zonaria lobata, bearing no 
inapt resemblance to those richly zoned and velvetty fungi 
which grow out of old dead tree-trunks; but both these 
lovely alge are tropical and belong to our most southern 
states. The rest of the Melanosperms are either parasitic 
and minute, and to be gathered either accidentally or else 
