854 The Philippine Journal of Science 1915 
of screens. This work should not be delayed until planting, 
when time is valuable. 
The water-gravity method is a very speedy and thorough 
way of cleaning palay. Small amounts may be placed in jars, 
buckets, or troughs of water. The small, immature, or undesir- 
able grains and light foreign matter will rise to the top. and 
overflow or they can be removed. The seed should not be in 
the water longer than the work requires and should be dried 
thoroughly and quickly. This process may be carried on at any 
time, as it in no way injures the seed. 
When there are several cavanes® of palay to be cleaned, the 
grain may be taken to a fanning mill—which is usually avail- 
able—where the work may be done at small expense. 
FACTORS WHICH SHOULD GOVERN THE SELECTION OF STANDARD 
VARIETIES OF RICE 
PRODUCTION 
In determining the value of any variety of rice, yield is of 
first consideration. The tendency to yield well or to withstand 
adverse conditions may be the deciding factor in favor of re- 
taining varieties which, on account of inferior quality, un- 
desirable color of cuticle, or low percentage of grain, would 
otherwise be eliminated. A heavy crop of even inferior quality 
is more desirable than a small crop of high quality. 
However, a variety must be such that it will produce big crops 
in the average season, not in a few especially favorable seasons 
only. 
In every province a large number of varieties are regularly 
planted which cannot, or do not, produce normal crops except 
in an unusually favorable season. For example, in some regions 
there is regularly planted a six-months rice which will not have 
sufficient rainfall to produce a normal crop one year in ten. 
A variety may be prized by the best markéts and yet its pro- 
duction may be unprofitable on account of poor yield, more or 
less loss in harvesting, due to a tendency to shatter, or because 
of a high percentage of breakage in milling. Long, slender 
grains break very readily (Plate I, fig. 3). Varieties of rice 
having grains about 7 mm in length and 3.5 mm in width and 
as thick as possible will better withstand the milling process. 
These varieties produce the maximum amount of head rice,* 
which largely determines the value of a crop. 
* One cavan equals 25 gantas, equals 75 liters. 
°The head rice is the whole rice left in the milling process, 
