It is impossible for us here to deal with the question of the origin of the parasitic habit in bees. The reader wishing for information as to this may refer to Prof. Pérez's paper, Act. Soc. Bordeaux, xlvii. 1895. p. 300.
Refer to p. [70] postea, note, as to a recent discovery about Xylocopa.
Souvenirs entomologiques. 4 vols. Paris, 1879 to 1891.
The "Chalicodome des galets" or C. "des murailles" of the French writer; in some places he speaks of the species as being C. muraria, in others as C. parietina.
Trans. Zool. Soc. London, vii. 1870, p. 178.