Page:Great Neapolitan Earthquake of 1857.djvu/224

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174 DIVISION OF FORMATIONS. slight difficulty in establishing a division in these sedimentary rocks, according to the order in which they have been deposited; and the ditculty has not been dlmlnihed by comparing them with rocks of determined epoch, which might be contemporary with oura For us, who have not had the advantage of seeing in their natural position any of the various sedimentary formations (except thoe of the irlnclom of Naples the difficulty has been still greater, nor can we flatter ourselves that we have surmounted iL Meanwhile, without entering into discussions which would be foreign to the principal aim of our work, but keeping to what appears to us to agree with our olarvations, we prefer to divide our neptamian rocks into three series, that is, three distinct forma- tiona In the first series we shall include all thoe calcareous rocks which are particularly characterized by Nummulites, Nerinee, and those organic forms of which we have no es-ple in the fauna of the present epoch, and which paleontologists, uncertain of their real nature, have denominated rdlmentary. (Rud/zt/.) The greater part of our Apennlne mountains being formed of this calcareous rock, we Rh11 retain for it exclusively the name of (Oa/rea Apennia) Apennine limestone. The rocks of the second series, very varied in their mlneralogical composition, agree in being distinctly stratified, in being almost entirely destitute of animal fossils. and in sometimes containing a great q,*antity of vegetable foils of the Fucoid order. Although it is not easy to find Fuciform impres- sions everywhere in rocks of this formation, nothing better indi- cates their cJmmcr than the presence of these plants; for the absence or extreme rarity of animal fossils is a negative charac- teristic which in exceptional cases rosy be atFmned of every species of rock. The last series comprehends mrls, limestone, and sand- stone, abounding in m_rine fossils, the greater number of which belong to species which now exist in our seaa To theze rocks we shall conne the name sub-Apennioe, although others else- where have designated some of the rocks of the preceding series with this denomination. They undoubtedly belong to the super- cretaceous period; and ff the igneous phenomena of Epomeo in the Phlegrean region, as we have shown elsewhere,* have pre-

  • Scacchi. ' Geological Memoir of Campania.' Naples: 1849. Pp. 19, 20.