Thus we find what the Leaf-cutters taught us proved, in another way, by the cotton-gatherers. In the local flora, the insect has no precise domain; it reaps its harvest readily now from one species, now from another, provided that it find the materials for its manufactures. The exotic plant is accepted quite as easily as that of indigenous growth. Lastly, the change from one plant to another, from the common to the rare, from the habitual to the exceptional, from the known to the unknown, is made suddenly, without gradual initiations. There is no novitiate, no training by habit in the choice of the materials for the nest. The insect's industry, variable in its details by sudden, individual and non-transmissible innovations, gives the lie to the two great factors of evolution: time and heredity. CHAPTER 10. THE RESIN-BEES. At the time when Fabricius (Johann Christian Fabricius (1745-1808), a noted Danish entomologist, author of "Systema entomologiae" (1775).--Translator's Note.) gave the genus Anthidium its name, a name still used in our classifications, entomologists troubled very little about the live animal; they worked on corpses, a dissecting-room method which does not yet seem to be drawing to an end. They would examine with a conscientious eye the antenna, the mandible, the wing, the leg, without asking themselves what use the insect had made of those organs in the exercise of its calling. The animal was classified very nearly after the manner adopted in crystallography. Structure was everything; life, with its highest prerogatives, intellect, instinct, did not count, was not worthy of admission into the zoological scheme. It is true that an almost exclusively necrological study is obligatory at first. To fill one's boxes with insects stuck on pins is an operation within the reach of all; to watch those same insects in their mode of life, their work, their habits and customs is quite a different thing. The nomenclator who lacks the time--and sometimes also the inclination--takes his magnifying-glass, analyzes the dead body and names the worker without knowing its work. Hence the number of appellations the least of whose faults is that they are unpleasant to the ear, certain of them, indeed, being gross misnomers. Have we not, for instance, seen the name of Lithurgus, or stone-worker, given to a Bee who works in wood and nothing but wood? Such absurdities will be inevitable until the animal's profession is sufficiently familiar to lend its aid in the compiling of diagnoses. I trust that the future will see this magnificent advance in entomological science: men will reflect that the impaled specimens in our collections once lived and followed a trade; and anatomy will be kept in its proper place and made to leave due room for biology.