In every barrel of meal or flour sent to market (196 pounds), there are not far from 186 pounds of carbon (coal), and the elements of water.  When a bird eats wheat or corn, I have reason to believe, from several experiments, that over 80 per cent, of the food escapes into the air through its capacious lungs in the process of respiration; and yet the 20 per cent, of guano left will re-produce as much wheat or corn as was consumed.  Imported guano, which has been exposed to the weather for ages, often gives an increase in the crop of wheat equal to three pounds of seed to one of fertiliser; while it has given a gain of seven to one of corn, and fifty to one of green turnips.

Like other grains that have been long cultivated, Indian corn abounds in varieties.  In Spain they count no less than 130, and in the United States the number is upwards of forty.  The difference consists in size, color, period of maturation, and hardness and weight of grain.  Of size there exists a considerable variety, from Zea Curagua of Chili, and the Egyptian or chicken corn, both extremely diminutive, to the large white flint, and ground seed corn of the United States.  The differences in color are the red, yellow, and white.  The period of maturation varies, apparently, very considerably; but it is questionable whether this variation is real, and independent of climate.  In the Northern States of America, Indian corn ripens in a shorter period of time than it does in the South, owing, possibly, to the greater length of the summer day in those latitudes.

In selecting varieties, some experienced and judicious farmers prefer that which yields the greater number of ears, without regard to their size, or number of rows.  Others prefer that which furnishes one or two larger ears, having from twelve to twenty-four rows.  In the Northern States of America the yellow corn bears the highest price in the market, and is considered the most prolific and best suited to feed cattle and hogs.  For bread, the white Button is preferred at the North, and the white ground seed is used for that purpose in other quarters.  Preference, however, is most frequently given to white flint corn, which is unquestionably the heaviest, and contains the greatest proportion of farina.

In Mississippi many varieties are grown, principally those known as flint and bastard flint.  The gourd-seed varieties are very objectionable in that climate, principally on account of their softness rendering them unfit for bread, and open to the attacks of insects in the field and the crib.  They require a grain, white, hard, and rather flinty—­white because of its great consumption in bread and hommony, in the preparation of both of which their cooks greatly excel.  When meal is ground for bread, the mill is set rather wide, that the flinty part of the grain may not be cut up too fine, this being sifted out for “small hommony;” the farinaceous part of the grain is left for bread.  This hommony