Where the space for pigeons is very limited and there is room for only one small loft and fly, breeding operations are closely restricted. Most pigeon fanciers want at least two lofts of this size--one for the breeding birds, the other for the young birds that no longer need the care of their parents. With such facilities the work in the breeding loft goes on better, and promising young birds can be kept until they are well matured and the breeder can tell whether it is advisable to keep some of these and dispose of a part of the old ones. To provide for larger numbers of birds, either more lofts or larger lofts may be made. A breeder of fancy pigeons usually prefers many small compartments. A breeder of squabs for market makes each compartment as large as is convenient and builds as many as he has room for. [Illustration: Fig. 209. Old poultry house arranged for pigeons. (Photograph from Dr. J. G. Robinson, Pembroke, Massachusetts)] Buildings for pigeons are constructed on the same plans as buildings for fowls. The furnishings of the pigeon loft are different from those of the poultry house, and of course the fly is always completely inclosed. Upper floors or lofts of buildings are used for pigeons to much better advantage than for poultry, but where there is room it is more satisfactory to have all quarters for pigeons on the ground floor. As the young pigeons remain in the nest and are fed by the parents until they are almost full-grown, each pair of old pigeons must have their own nesting place. As has been stated, the domestic pigeon is a shelf builder. So in arranging for nests the pigeon keeper builds shelves 10 or 12 inches apart, and divides these into compartments about 12 inches wide, thus forming pigeonholes. Because a hen pigeon often lays again and begins to incubate before a pair of young are ready to leave the nest, it is usual to arrange the pigeonholes in pairs. This is sometimes done by omitting alternate dividing boards, making each pigeonhole twice the size required, so that a nest can be made in each corner. Some people prefer to have single pigeonholes and to arrange them in double sections by making each alternate perpendicular board project several inches beyond the front edge of the horizontal shelf. When this is done, a pair of pigeons in possession of one side of a double section will usually claim the entire section and prevent others from entering it even when they are themselves using only one side. [Illustration: Fig. 210. City back-yard squab plant]