360 
POLYNESIAN RESEARCHES. 
generally spread over them about an inch in thick¬ 
ness. 
The yam is one of the best flavoured and most nu¬ 
tritive roots which the islands produce. The natives 
usually bake them; they are, however, equally good when 
boiled ; and, as they may be preserved longer out of the 
ground than any other, they are the most valuable sea- 
stock to be procured; and it is to be regretted that they are 
not more generally cultivated. Few are reared in the 
Georgian Islands ; more perhaps in the Society cluster ; 
but Sir Charles Sander’s Island is more celebrated for 
its yams than any other of the group. 
The umara^ or sweet potato, convolvulus hatatus, or 
chrysorizus, is grown by the natives as an article of food. 
The richest black mould is chosen for its culture; and 
the earth is raised in mounds nine or ten feet in 
diameter, and about three feet high. They do not plant 
the roots; but in the top of these mounds insert a 
small bunch of the vines, which germinating, produce the 
tuberous roots eaten by the natives. In the Sandwich 
Islands, the sweet potato is one of the principal means 
of subsistence; here it is only partially cultivated, and 
is greatly inferior to those grown in the northern islands, 
probably from the difference of soil and climate. The 
roots are large, and covered with a thin smooth skin. 
In size, shape, and structure, they resemble several kinds 
of the Irish potato. The umara is very sweet, seldom 
mealy, and sometimes quite soft, and altogether less 
palatable than the taro or the yam. It is dressed by the 
natives in their stone ovens, and is only used when the 
bread-fruit is scarce. 
Patara, is a root growing wild in the valleys, in shape 
and taste resembling a potato more than any other 
