[Footnote 2: At Cutchavelly, north of Trincomalie, there exists a bed of calcareous clay, in which shells and crustaceans are found in a semi-fossilised state; but they are all of recent species, principally _Macrophthalmus_ and _Scylla_. The breccia at Jaffna contains recent shells, as does also the arenaceous strata on the western coast of Manaar and in the neighbourhood of Galle. The existence of the fossilised crustaceans in the north of Ceylon was known to the early Arabian navigators. Abou-zeyd describes them as, "Un animal de mer qui resemble à l'écrevisse; quand cet animal sort de la mer, _il se convertit en pierre_." See REINAUD, _Voyages faits par les Arabes_, vol. i. p. 21. The Arabs then; and the Chinese at the present day, use these petrifactions when powdered as a specific for diseases of the eye.] _Mountain System_.--At whatever period the mountains of Ceylon may have been raised, the centre of maximum energy must have been in the vicinity of Adam's Peak, the group immediately surrounding which has thus acquired an elevation of from six to eight thousand feet above the sea.[1] The uplifting force seems to have been exerted from south-west to north-east; and although there is much confusion in many of the intersecting ridges, the lower ranges, especially those to the south and west of Adam's Peak, from Saffragam to Ambogammoa, manifest a remarkable tendency to run in parallel ridges in a direction from south-east to north-west. [Footnote 1: The following are the heights of a few of the most remarkable places:-- Pedrotallagalla 8280 English feet. Kirrigalpotta 7810 English feet. Totapella 7720 English feet. Adam's Peak 7420 English feet. Nammoone-Koolle 6740 English feet. Plain of Neuera-ellia 6210 English feet.] Towards the north, on the contrary, the offsets of the mountain system, with the exception of those which stretch towards Trincomalie, radiate to short distances in various directions, and speedily sink down to the level of the plain. Detached hills of great altitude are rare, the most celebrated being that of Mihintala, which overlooks the sacred city of Anarajapoora: and Sigiri is the only example in Ceylon of those solitary acclivities, which form so remarkable a feature in the table-land of the Dekkan, starting abruptly from the plain with scarped and perpendicular sides, and converted by the Indians into strongholds, accessible only by precipitous pathways, or steps hewn in the solid rock.