Molluscs are extraordinarily numerous; and many, both of water and land, are rarities among their kind for size and richness of colour.
Absolutely colourless stones are not so common as cloudy and faintly coloured specimens; the usual tints are grey, brown, yellow or white; and as rarities, red, green, blue and black stones have been found.
But there are records of expeditions sent out by the king to obtain the rarities of different countries, and the hero of the Story of the Shipwrecked Sailor was upon this quest.
The Nile valley afforded a passage by ship or on foot into Nubia, where, however, little wealth was to be sought, though gold and rarities from the Sudan, such as ivory and ebony, came that way and an armed raid could yield a good spoil in slaves and cattle.
4 I 1672 Josselin (New England's Rarities, p. 9) speaks of the settlers bringing up " great store of the wild kind " of turkeys, " which remain about their houses as tame as ours in England."