Those grains which grow on a stalk of straw are enclosed in an envelope protected by a prickly beard; while in the bean and the leguminous plants in general they are enclosed in pods upon branches which shoot alternately from either side. The cereals are the best able to withstand the winter, but the leguminous plants afford the most substantial food. In wheat, the grain has several coats, but in barley,[118] more particularly, it is naked and exposed; the same, too, with arinca,[119] but most of all, the oat. The stem is taller in wheat than it is in barley, but the ear is more bearded[120] in the last. Wheat, barley, and winter-wheat[121] are threshed out; they are cleaned, too, for sowing just as they are prepared for the mill, there being no necessity for parching[122] them. Spelt, on the other hand, millet, and panic, cannot be cleaned without parching them; hence it is that they are always sown raw and with the chaff on. Spelt is preserved in the husk, too, for sowing, and, of course, is not in such case parched by the action of fire. CHAP. 11.—SPELT. Of all these grains barley is the lightest,[123] its weight rarely exceeding fifteen pounds to the modius, while that of the bean is twenty-two. Spelt is much heavier than barley, and wheat heavier than spelt. In Egypt they make a meal[124] of olyra,[125] a third variety of corn that grows there. The Gauls have also a kind of spelt peculiar to that country: they give it the name of “brace,”[126] while to us it is known as “sandala:” it has a grain of remarkable whiteness. Another difference, again, is the fact that it yields nearly four pounds more of bread to the modius than any other kind of spelt. Verrius states that for three hundred years the Romans made use of no other meal than that of corn. CHAP. 12.—WHEAT.