Page:Popular Science Monthly Volume 15.djvu/790

770 and then destroyed the whole edition a few days afterward, because he could find only six purchasers of the work, to the preparation of which he had devoted twenty years of his life! These organisms were as poorly appreciated then as now. Max Shultze reports that he has separated 1,500,000 specimens from one ounce of sifted sand from the coasts of Italy, near Mola di Gaeta. Also the deep-sea sands are in great part made up of their shells. In most of these the perforated forms abound, but in many localities the silicic symmetrical frames are most numerous. Until recently the great depths of the ocean were supposed to be dark, barren wastes; that the lack of oxygen, with the immense pressure of water from above, rendered these abysses impenetrable and uninhabitable. But the success of modern deep-sea soundings, particularly in the region of the Atlantic cable, has shown that the Atlantic ooze or chalk-mud, of which the ocean-bed is so largely composed, is literally alive with protoplasmic animalcules, whose innumerable shells and calcareous deposits give to this ooze its peculiar character, and are virtually constructing beds of chalk. These and other facts have led some of our best authorities to believe that the formation of chalk has been a continuous process from the Cretaceous time to the present.

In their geographical distribution most have an extremely wide range, and great numbers of species are cosmopolitan in their occurrence, yet there is a general uniformity of the conditions under which they exist. For example, globigerina appears often in such great depths of the ocean that the temperature of its habitat hardly varies with the seasons, or even for different zones, while the same species under different conditions of depth, temperature, etc., does show very strong varieties, which are sometimes so markedly distinct as to be accounted different species and genera, as has often been asserted by Carpenter, Williamson, and others. Professor Carpenter also states that Messrs. Parker and Jones became so familiar with the geographical variations of the species of perforated shells, that they could judge from the appearance of a specimen whence it came.

The infusorians belong chiefly to the fresh water, being plentiful in all lakes, ponds, swamps, rivers, and smaller streams, while only a few are marine; contrariwise, the rhizopods are mostly found in the seas, a small number inhabiting fresh waters. The rhizopods also serve an important function in the depths of the sea by setting free in the water large supplies of carbonic and phosphoric acids. Certain infusorian lash-swimmers (noctiluca, etc.) sometimes make the ocean look red or bloody by day and illumine it with phosphorescence at night. This is often observed in the Red Sea, in the Gulf of Guinea, off the north of France, on the Peruvian coasts, and in the Gulf of California, which on this account was called Mar Vermijo, or Vermilion Sea, by the early Spanish navigators.

With few exceptions, microscopic beings possess the power of