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Show COLOES VARIED AT WILL. Butterflies of Any Desired Species Produced by Scientist. A discovery of the greatest Importance lo zoology, nothing less. In fact, than tho production of varieties of butterflies simply by the use ofchanges of temperature tempera-ture of the chrysalides and cocoons. Is : announced In Xuova AntolOgla of Rome. Such experiments are peculiarly Intercst7 Ing, In view of tho recent work nnd theories of Prof. Hugo Do Vrles of Amsterdam, Am-sterdam, on tho subject of species and variation. , For a long lime work In zoology haa been centered upon classification, but now the study has become an experimental one, and In this new road Prof. Standfuss of Zurich has obtained some remarkablo results. It seems that certain species of butterflies hnvo successive and different generations, the chrysalides of thd vanessa lavana, for example, producing in the spring a bultcrlly which deposits Its egg in summer, and from which there Is born in the same year a butterlly which differs entirely In form nnd color from the first generation. Now. If we submit tho autumn egg lo si high temperature. SO decrees Fahrenheit, tho butterlly which Is born has the same form and color as tho summer Insecl. The same result Is obtained with tho vanessa urticae. which is found under different dif-ferent forms at tho North Capo and in Sardinia. By cooling the air In which the egg, cocoon or chrysalis la placed there Is obtained the northern form of the butterlly, while if wc warm the egg or cocoon to SC degrees Fahrenheit the Southern form comes into exlstcnco. A splendid experiment Is tho ono which may be performed with tho macaone. In this case ono need only raise the tomperaturo to obtain the beautiful form of tho butterfly but-terfly which lives In the Orient; exposing the chrysalis alternately to temperatures of -10 degrees abovo zero centigrade and 40 degrees below, wo obtain an ancient spcclcB which Is no longer in existence. This experiment was made by Standfuss on from nix to seven thousand cocoons and chrysalides, and ho succeeded in obtaining ob-taining the greater portion of tho species of the past as woll as some of the new species, and this to such a degree that he could clearly demonstrate the effect of heredity. Not only differences of tomperaturo, however, but also the chemical composition compo-sition of tho air, has Us effect on I ho chrysalis and produces a variation In tho development. It is possible simply by changing tho chcmlca.1 composition of the air to chango entirely the color of the butterfly. 9 |