with strange words, as if he purposely would permit a glance into the treasures of his science and his knowledge only to an extremely narrow circle. Nothing better shows this than the style of most of our (German) text-books when compared with that of the majority of the English books, which nevertheless are not behind ours in thoroughness. Even once to write something "popular"—who does not know how many of our students look loftily down upon this art? Now I think it is a valuable art, and worthy of recognition. It can not be expected that every one shall become possessed of it, and every one shall exercise it; but the art is very often wanting simply because exclusive devotion to "purely scientific" work in some extremely narrow field of knowledge has prevented its ever having been put in practice. Many also deliberately hold themselves aloof from it because whoever among us writes understandingly to the public appears to compromise his reputation as a man of science.
Why is it entirely different in England ? Why do the first men of science there—those who are recognized and admired by the German scientific world—write understandingly to every one? Who does not enjoy the famous essays of Faraday on "A Candle," of Tyndall on "The Forms of Water," of Huxley on "The Crayfish," etc.? I do not forget that there are also a few scientific men having this talent among us, but they do not escape the shrugs of their contemporaries. It is true that a student who should make such general representation his principal work would soon forfeit his importance as an investigator. But it is also desirable, on the other hand, that the naturalist should not exhaust himself in the examination of details, but that he should, for the sake of keeping himself fresh, come forward with his conclusions from time to time immediately before the cultivated world, and not let the great value of his investigations be recognized by strangers only. In sequence with this general reserve of students—besides the resulting deficiencies in scientific school-instruction—exists also a backwardness among our laymen in expressing themselves respecting their observations of Nature. Nature invites every one to observation and reflection; and even the inexpert inquirer is not excluded from the privilege of being led up to the noblest experiences through this observation and reflection. What does not scientific zoölogy, to mention but one example, owe to the bee-master. Pastor Dzierzon, for his determination of the parthogenesis of bees? And did not Goethe, without being a professional naturalist, arrive at his famous fruitful ideas of the composition of the skull out of vertebrae, of the human intermaxillary, and of the tracing of the parts of the plant back to the leaf? He repeatedly expresses in plain terms the thought of the unity of all Nature and of the continuous development of her forms, on grounds not of pure speculation, but of observation and reflection upon it. Darwin's corresponding conclusions also originated from the simplest observations that presupposed no scientific