44 . BOTANICAL GAZETTE [JANUARY 
most extensive coral reefs. At the other extreme stands Hawaii; 
the youngest, highest, and largest island in the archipelago, with 
practically no lowlands or coral beaches, and very little reef coral. 
The oldest islands of the series are the tiny reefs and shoals 
dotted along an axis 1800 miles long, lying to the west of the main 
group. Although of little commercial value, and with a combined 
area of only 6 square miles, these little islands are of great interest 
from the standpoint of their alga flora. Nihoa, French Frigates 
Shoal, and Gardner are eroded volcanic blocks, 170-900 ft. high, 
rimmed with fringing coral. Laysan and Lisianski are elevated 
coral islands, 45-55 ft., with fringing reef. Pearl and Hermes, 
Midway, and Ocean are typical coral atolls. Maro and Dowsett’s 
reefs have visible surf, but no exposed coral. The entire series, 
named in sequence from east to west, is Nihoa, Necker, French 
Frigates Shoal, Gardner, Dowsett’s Reef, Maro Reef, Laysan, 
Lisianski, Pearl and Hermes Reef, Midway, Ocean. SCHAUINS- 
LAND" spent three months on Laysan and made extensive collections 
of the marine flora, both plankton and larger forms, but no thorough 
explorations have been made of the algae on the other isles and 
reefs.2. When such an exploration, or series of explorations, is 
made, there is not the slightest doubt that a large number of new 
forms will be revealed, and that very important contributions will 
be made to the algology of the Central Pacific region. The signifi- 
cant feature of this long chain of tiny islets is that it undoubtedly 
represents the various stages in the subsidence of a titanic sub- 
marine mountain chain. 
Some of the representative forms collected by SCHAUINSLAND 
at Laysan, and therefore to be expected along the shores and in 
the lagoons of others of these westward isles, are Chondrocystis 
Schaunslandii, Gomphospharia beset eee scribd hiv holo praia, 
Xenococcus laysanensis, Oscillatoria 
sima, Phormidium laysanense, Lyngbya mucicola. - meneghiniana, 
Aulosira Schaunslandii, Caulerpa pinnata, ahs lobatum, 
and Liagora coarctata. 
* SCHAUINSLAND, H. H., Drei Monate auf einer Korallen Inseln. Bremen. 1899- 
* MacCaucuey, VaucHAN, The little end of Hawaii. Jour. Geog. 15:23~26. 
1916; also Outstanding biological features of the Hawaiian Archipelago, in press. 
