1918] MAcCCAUGHEY—HAWAIIAN ALGAE 143 
Rhodophyceae 
BANGIACEAE 
Porphyra leucosticta Thuret.—This is the famous limu lua’u 
of the Hawaiians, a very highly prized delicacy. It appears in late 
winter or early spring after the heavy southerly storms, and lasts 
for only a few days. It is found only on exposed rocks constantly 
dashed by the waves, so it is difficult and dangerous to collect, 
especially as the alga is extremely slippery and has to be scraped 
forcibly from the rocks in small bunches while the collector clings 
to his support and avoids the heavy waves. REED states as 
follows: 
He must be sure-footed, quick, and a good swimmer, if he collect limu 
luau. ... . It is prepared by washing in the usual way in fresh water. It 
is then salted a little and put into clear water, where it becomes slippery and 
colors the water a lovely violet color. Sometimes opihi, a kind of limpet, is 
put in with the limu and salt in water, and placed in bottles or jars. This is 
used as needed, for it keeps many weeks when placed in the weak brine with 
the limpets. | 
Limu luau is considered a great delicacy in the few localities where it 
occurs, but it lasts so short a season, is so scarce, and so difficult to get that it 
is not very widely known. Only on northern Kauai, northern Maui, and 
northern Hawaii is it in use or in great favor, as it does not occur in other places, 
except a few scattered plants on Oahu and Molokai. 
HELMIN THOCLADIACEAE 
Liagora valida Harv.—Collected at Laysan; also occurs in the 
Atlantic and around Madagascar; often calcareous. 
L. coarctata Zanard.—Collected at Laysan. 
L. decussata Mont.—Called limu pu-aki by the natives, and 
considered edible; grows along the coral reefs in quiet shallow 
water, often in mud or sand or on small stones; fronds filiform, 
virgate-ramified, calcareous. 
CHAETANGIACEAE 
Galaxaura lapidescens (Soland) Lamx.—Fronds cylindric or 
compressed, subtubular, incrusted with lime; along the coral reefs 
in shallow waters; a common species in warm seas. 
G. spongiosa Kuetz.—Habitat same as the preceding. 
