GUINEA, a gold coin at one time current in the United King dom. It was first coined in 1663, in the reign of Charles II., from gold imported from the Guinea coast of West Africa by a company of merchants trading under charter from the British crown—hence the name. Many of the first guineas bore an ele phant on one side, this being the stamp of the company; in a castle was added. Issued at the same time as the guinea were five-guinea, two-guinea and half-guinea pieces. The current value of the guinea on its first issue was twenty shillings. It was subsidiary to the silver coinage, but this latter was in such an unsatisfactory state that the guinea in course of time became over-valued in relation to silver, so much so that in 1694 it had risen in value to thirty shillings. The rehabilitation of the silver coinage in William III.'s reign brought down the value of the guinea to 21s. 6d. in 1698, at which it stood until 1717, when its value was fixed at twenty-one shillings. This value the guinea retained until its disappearance from the coinage. It was last coined in 1813, and was superseded in 1817 by the sovereign. In 1718 the quarter-guinea was first coined. The third-guinea was first struck in George III.'s reign (1787). To George III.'s reign also belongs the "spade-guinea," a guinea having the shield on the reverse pointed at the base or spade-shaped.
a well-known gallinaceous bird, so called from the country whence it was brought to Europe. It was known to the Romans but was probably reintroduced by the Portuguese in the 16th century.
The ordinary guinea-fowl of the poultry-yard (see also POULTRY AND POULTRY-FARMING) is Numida meleagris. Under domesti cation few varieties have arisen. We may mention total and partial albinism and forms with legs bright orange instead of greyish brown. The sexes are alike. The home of this species is West Africa from the Gambia to the Gaboon. It has been imported into the Cape Verde islands, where, as in some of the Greater Antilles and in Ascension, it has run wild. Representing the species in South Africa we have N. coronata which is numerous from the Cape Colony to Ovampoland, and N. papil lose which replaces it in the west as far as the Zambesi. Madagascar has N. mitrata, distinguishable by its red crown and extending to East Africa. This bird has been introduced to Rodriguez. Abyssinia is inhabited by N. ptilorhyncha, which differs from the foregoing by the absence of red about the head. Darwin (Anim. and Pl. under Domestication, i. 294), gives this as the original stock of the modern domestic birds, but obviously by an accidental error. The finest species known is Acryllium vulturinum of Somaliland, conspicuous by the bright blue in its plumage, the hackles in the lower part of its neck, and its long tail. All these guinea fowls except the last are characterized by having the crown bare of feathers and elevated into a bony "helmet," but there is another group in which a thick tuft of feathers ornaments the top of the head. This contains four or five species inhabiting Africa, the best known being Guttera cristata from Sierra Leone. This bird is remarkable for the structure of its furcula, or merry thought, where the head is a hollow cup opening upwards, into which the trachea dips, and then emerges on its way to the lungs. Allied to the genus Numida, but distinguished therefrom by the possession of spurs and the absence of a helmet are Agelastes and Phasidus, from western Africa.
Polygamous and gregarious, guinea-fowls lay many eggs on the ground. The flocks are noisy. The birds feed on the ground but normally roost in the trees.