. The Quarterly journal of the Geological Society of London . t strata occurred before the deposition of the next series. The Khirthar series in its highest portion a massive, paleor dark grey, hard, compact jSTummulitic limestone whose extremethickness is 3000 feet. It thins out to the south-west, and disap-pears within a distance of twenty-five miles of its greatest develop-ment. Other ISFummulitic limestone-beds are found, which may belower in the series ; and they and the main group are representedelsewhere by shaly limestones and sandstones with calcareous some district
. The Quarterly journal of the Geological Society of London . t strata occurred before the deposition of the next series. The Khirthar series in its highest portion a massive, paleor dark grey, hard, compact jSTummulitic limestone whose extremethickness is 3000 feet. It thins out to the south-west, and disap-pears within a distance of twenty-five miles of its greatest develop-ment. Other ISFummulitic limestone-beds are found, which may belower in the series ; and they and the main group are representedelsewhere by shaly limestones and sandstones with calcareous some districts flint occurs in a limestone with Alveolince. Thelower members of the series are often wanting, and are well repre-sented by shales, marls, and sandstones and where these are present;unconformity with the underlying .Eanikot beds is not seen; butwhere they are absent the j^ummulitic limestone (as in the Lakirange) rests unconformably. The compact limestone is of course-* Memoirs Geol. Survey of India, vol. xvii, pt. 1, p. 131. 194 PROF. P. M. DUNCAN OX THE. C0RALL1EE110US SERIES OF BIND. 195 highly fossiliferous; but it has not yielded very good specimens ofCorals. The indications of a fringing-reef-buildirig fauna, or a bankof coral, are distinct; but the species when compared with theirmodern analogues do not indicate a great other fossils, Lamellibranchiata prevail, and the Echini arenumerous; but the jNumnnilitcs and Orbitolites, Alveolince, andPatellince are the most important organic remains. Amongst theNummiilites there are N. Bamondi, iV. biaritzensis, iV. Beaumonti,N. granulosus, and N. Leymeriei. The ]STari series rests conformably on the Khirthars ; and there isoccasionally an apparent passage from the Khirthar limestone into ayellow or brown rock of the ISTari group. There is, however, abiological break; for the Juimmulites of the upper group arocharacteristic, and differ from those of the lower. The Khirtharforms are not found, and Nummidi
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