The heads are cut when ripe and tied in bundles to dry, after which the grain is readily beaten out in wooden mortars or with sticks. The flour made from the grain is ground between stones, and is frequently eaten in the form of a thin porridge. Two varieties of Nigerian Guinea corn have been examined at the Imperial Institute and shown to be superior to Indian Guinea corn, though not quite so good as the Syrian grain (_Bulletin of the Imperial Institute_, vol. vii. [1909], p. 148.) Smut-blights, _Ustilago Reiliana_ and _Tolyposporium sp._ (called in Haussa “domana”), attack the heads, and a _Capnodium sp._ (called “derba”), the honeydew produced on the leaves by _Aphis sorghi_ (cf. _Bull. Imp. Inst._, vol. xi. [1913]). At certain stages, green Guinea corn is poisonous to cattle, and for this reason goats, sheep, and cows are muzzled in the Kano and Zaria Provinces. Local knowledge of this fact confirms what has been observed elsewhere with regard to this species, and is explained by investigations conducted at the Imperial Institute. (_Bulletin of the Imperial Institute_, vol. i. [1903], and vol. viii. [1910].) =BULRUSH MILLET.=—This plant, which is supposed to be of African origin and is usually called millet in West Africa, belongs to that group of grasses of which the seeding head is in a compact form and in appearance resembles the head of a bulrush, from which the common name applied to it has been derived. The botanical name is _Pennisetum typhoideum_, and the plant is known in the country as “Gero” or “Giro” (Haussa), and in India as “Bajra.” At least two varieties, a smooth and an awned form, are grown as three-months’ crops, and are sown either alone or as described before with Guinea corn. It is usual to plant millet seed before the Guinea corn, generally about the middle of April, or as soon as the first showers are experienced. The crop is then ready for picking in June and July. If the rainfall by this time has been deficient to such an extent that the Guinea-corn crop promises to prove a failure, a second crop of millet is often put in, and, as very much less rain is required for this crop than is necessary for Guinea corn, the severe effects of a short rainfall are minimised. The grain yielded by _Pennisetum typhoideum_ would be classed commercially as a millet, and a sample from Nigeria examined at the Imperial Institute was valued at 22_s_. per quarter of 480 lb. (July 1908). In addition to the two varieties mentioned which are employed as three-months’ crops, there is another kind with a smooth greyish-white large grain which is called “Maiwa” or “Dauro,” and is cultivated in the same manner as Guinea corn; occupying the land for from five to six months. The pagan Gwaris to the south of Zaria grow this in large quantities, but it is uncommon north of Zaria.