southern and eastern Alps to Egypt, Sinai, and on to north India. The peculiar structure occurring in the Lower Laurentian limestone, as well as other limestones of Archean age described as a Nummulitaceous genus, "_Eozoon_," by Carpenter and Dawson, and abundantly illustrated in the 9th edition of his encyclopaedia, is now universally regarded as of inorganic origin. "Looking at the almost universal diffusion of existing Foraminifera and the continuous accumulation of their shells over vast areas of the ocean-bottom, they are certainly doing more than any other group of organisms to separate carbonate of lime from its solution in sea-water, so as to restore to the solid crust of the earth what is being continuously withdrawn from it by solution of the calcareous materials of the land above sea-level." (E.R. Lankester, "Protozoa," _Ency. Brit._ 9th ed.) [Illustration: FIG. 22.--Imperforata. 1, _Spiroloculina planulata_, Lamarck, showing five "coils"; porcellanous. 2, Young ditto, with shell dissolved and protoplasm stained so as to show the seven nuclei n. 3, _Spirolina_ (_Peneroplis_); a sculptured imperfectly coiled shell; porcellanous. 4, _Vertebralina_, a simple shell consisting of chambers succeeding one another in a straight line; porcellanous. 5, 6, _Thurammina papillata_, Brady, a sandy form. 5 is broken open so as to show an inner chamber; recent. X 25. 7, _Haplophragmium canariensis_, a sandy form; recent. 8, Nucleated reproductive bodies (bud-spores) of _Haliphysema_. 9, _Squamulina laevis_, M. Schultze; X 40; a simple porcellanous Miliolide. 10, Protoplasmic core removed after treatment with weak chromic acid from the shell of _Haliphysema tumanovitzii_, Bow. n, Vesicular nuclei, stained with haematoxylin. (After Lankester.) 11, _Haliphysema tumanovitzii_; X 25 diam.; living specimen, showing the wine-glass-shaped shell built up of sand-grains and sponge-spicules, and the abundant protoplasm p, issuing from the mouth of the shell and spreading partly over its projecting constituents. 12, Shell of _Astrorhiza limicola_, Sand.; X 3/2; showing the branching of the test on some of the rays usually broken away in preserved specimens (original). 13, Section of the shell of _Marsipella_, showing thick walls built of sand-grains.] [Illustration: FIG. 23.--Perforata. 1, Spiral arrangement of simple chambers of a Reticularian shell, as in small _Rotalia_. 2, Ditto, with double septal walls, and supplemental shell-substance (shaded), as in large _Rotalia_. 3, Diagram to show the mode in which successively-formed chambers may completely embrace their predecessors, as in _Frondicularia_. 4, Diagram of a simple straight series of non-embracing chambers, as in _Nodosaria_.