The above are organisms which can be seen only through the microscope, but the fauna of mines contains also larger organisms, though they are not found as regularly and are not as characteristic for those places as the forms mentioned hitherto. Among these organisms there are several species of worms, spiders, gnats, and, above all, crustaceans of the lower class. The most interesting of the latter is perhaps a variety of the sand flea (Fig. 8--_Gammarus pulex_). The crustacean found in the pits of mines, which is related to the sand flea, shows, according to Dr. R. Schneider, a slight degeneration of the organ of sight, which has taken place in consequence of its adaptation to the dark places, in which this variety of the _Gammarus pulex_ is found, which can make no use of eyes, while the sand flea possesses them fully developed. Otherwise, however, the two varieties are almost absolutely alike, differing only in some details. [Illustration: FIG. 8.--THE SAND FLEA (GAMMARUS PULEX).] From the above the reader will see that "breathing in the rosy light," as Schiller calls it, is not an absolutely necessary condition for the existence of organic beings, but that life exists everywhere, where there is air and moisture, and a temperature which is not always below freezing point, though even eternal frost does not exclude life entirely, as is proved by the existence of the glacier flea, showing that even in the icy coverings of the Alps life still is possible. Mephistopheles may therefore well say: "From water, earth, and air unfolding, A thousand germs break forth and grow In dry and wet, and warm and chilly; And had I not the Flame reserved, why really, There's nothing special of my own to show!" --_Leipziger Illustrirte Zeitung._ * * * * * [NATURE.] TIMBER, AND SOME OF ITS DISEASES.[1] [Footnote 1: Continued from Supplement, No. 661, page 10558.] By H. MARSHALL WARD. IX.