. The microscope and its revelations. or a detailed account of ,V. xj>lurrir« consult L. Rhmnbler, in vol. Ivii. of wins. Zonl. ARENACEOUS FOEAMINIFEKA 313 stance of which very fine sand-grains are dispersed. This felt issomewhat flexible, and its components do not seem to be united byany kind of cement, as it is not affected by being boiled in strongnitric acid; its tendency, therefore, seems entirely due to thewonderful manner in which the separate silicious fibres are is not a little curious that these two forms >hould present them-selves in the same dredging, and
. The microscope and its revelations. or a detailed account of ,V. xj>lurrir« consult L. Rhmnbler, in vol. Ivii. of wins. Zonl. ARENACEOUS FOEAMINIFEKA 313 stance of which very fine sand-grains are dispersed. This felt issomewhat flexible, and its components do not seem to be united byany kind of cement, as it is not affected by being boiled in strongnitric acid; its tendency, therefore, seems entirely due to thewonderful manner in which the separate silicious fibres are is not a little curious that these two forms >hould present them-selves in the same dredging, and that there should be no perceptibledifference in the character of their sarcode bodies, which, as in thepreceding case, have a dark-green hue. The Mfirsipdlri eloni/(it<t(fig. 614, d), on the other hand, is somewhat fusiform in shape. ;indhas its two extremities elongated into tubes, with a circular orificeat the end of each. The materials of the tests differ remarkablyaccording to the nature of the bottom whereon they live. When. Fi<;. 014.— Arenaceous Foraminifera: u, li, upper and lower aspects of/iJimgiiiiinn globigeriniforme, c, Hormosinu f/lolmJi/frn : </, Miirelongata ; e, terminal portion, and/, middle portion of the same, enlarged ;g, Thitrtinimina papillata ; /(, portion of its inner surface, enlarged. they come up with Globigerina mud. in which sponge-spiculesabound, whilst sand-grains are scarce, they are almost entirelymade up of the former, which are laid in a sort of lattice-work,the interspaces of which are filled up by fine xmd-gi-ains ; hut whenthey are brought up from a bottom on which sand predominates,the larger part of the test is made up of sand-grains mid minuteForaminifera, with here and there a sponge-spicule (fig. 614, d,f).In each case, however, the tubular extensions (one of which some-times forms a sort of proboscis, e, nearly equalling the body itselfin length) are entirely made up of sponge-spicules laid side by sidewith extraordinary
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmicrosc, bookyear1901
