. College collection of palaeontology. 162 PROTOZOA. The former include a large proportion of the Foraminifei-s which come under general observation, namely, the three families Lagenida^ Glohigerinida and Nummulinida. They are charac- terized by a calcareous shell perforated by tubular openings. The extraordinary multiplication of Nummulites in the Eocene gives the last family a place of no mean importance as a member of its fossil fauna. The imperforated Foraminifers include the families Gro7nida, Miliolida and Lituolida, in which the nature of the envelope is membranous, porcellanous or aren
. College collection of palaeontology. 162 PROTOZOA. The former include a large proportion of the Foraminifei-s which come under general observation, namely, the three families Lagenida^ Glohigerinida and Nummulinida. They are charac- terized by a calcareous shell perforated by tubular openings. The extraordinary multiplication of Nummulites in the Eocene gives the last family a place of no mean importance as a member of its fossil fauna. The imperforated Foraminifers include the families Gro7nida, Miliolida and Lituolida, in which the nature of the envelope is membranous, porcellanous or arenaceous. The Miliola is now the most universally diffused Foraminifer; its type can be traced back to the Lias. Upwards of 700 fossil species of Foraminifers have been de- scribed. They commence in the Palaeozoic, increase in number and variety with successive strata, and attain their maximum in the present seas. Indeed, they are so abundant in the most com- mon materials, as chalk for example, as to justify the expression of Buffon, th^t the very dust has been alive. The calcaire gros- sier—the building stone of Paris, and the material of the pyra- mids are full of these minute chambered shells; while the deep- sea soundings show that the bed of the Ocean is composed of little else than shells of Olobigerinm and the shields of Poly- cystinoB. No. 506. Eozoon Canadense, talline rocks of the Archaean of Nation, Canada. This has been described by Principal Dawson as a gigantic Foraminifer. Its organic nature is still doubted, and in the opinion of a large number of our best authorities, is entirely disproved. The fossil, if such it be, is described as con- sisting of a chambered calcareous skeleton, infiltrated by silicates, chiefly pyroxene, serpentine and Loganite, which occupy the spaces formerly filled by the sarcode of the living animal. These chambers are arranged in tiers, one above the other, and the fossil seems thus to have formed great reef-like masses, and m
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