The lamented Professor Perez was the teacher of Ferton. He had the same ideas and his biological observations were of the same thorough character. His observations on the variability of the instincts of the Osmias are of the greatest interest. He shows1 that Osmia rufa nests in any convenient cavity. It likes to repair old nests, but cut reeds, holes in boards, empty snail-shells, keyholes, appear to it to be excellent places to make its masonry cells. Fabre induced the Osmias to work in glass tubes. Perez says :
1 J. Pérez, Les) Abeilles, 1889.
They utilize the place to best advantage; the bee knows whether to arrange her cells in line in order to give them an exact cylindrical form when a narrow tube is used, or to place them without order when there is plenty of space. This total absence of exclusivism, this flexibility of architectural genius, surely does not conform to the theory of an unchangeable and blind instinct. To depart from its customary habit so easily, or, more, not to have any habit and to adapt itself without effort to the thousand conditions which chance offers, it is surely necessary to have a modicum of intelligence.