1855.] C. FORBES — NEW ZEALAND. 525 



a yellow clay-slate occurs, in some places intersected by veins of 

 quartz. In Port Underwood the slate is blackish-blue, and ap- 

 proaches somewhat to roofing-slate. 



From Port Underwood to Cape Campbell, a plain of the same cha- 

 racter as the Waimea is found. Towards the limestone country of 

 Cape Campbell, grassy downs are the prevailing features of the 

 country. The limestone which occurs there resembles chalk, con- 

 tains flints, and is fossiliferous ; a large species of Area and another 

 of Cardium often occur. The bones of the Moa are often found here. 

 To the southward of Cape Campbell the great range of the Kaikoras 

 mountains approaches the sea ; but a narrow belt of the chalky lime- 

 stone continues to form the sea- coast down nearly to Double Corner, 

 where the limestone is replaced by a calcareous and sometimes sandy 

 shell-rock, and by a tertiary blue clay with shells. The limestone is 

 associated with a white sandstone, and with a lignitic deposit which 

 exists a short distance inland. From Double Corner, the Port Cooper 

 Plains extend to the southward, bounded inland by a range of moun- 

 tains, thirty to fifty miles distant from the sea-coast. Here again 

 the same gravel formation exists, covered by alluvial deposits in the 

 neighbourhood of the rivers. The plains are much cut up by im- 

 mense dry water-courses, down which the mountain-torrents must at 

 one time have rushed in great floods. The rocks found in these 

 river-beds are quartz (of different colours), jasper, slates, and granitic 

 and trap rocks. 



In ascending the bed of the river Kohai to the foot of Mount 

 Grey, which lies about ten miles inland, and has an elevation of 

 about 3000 feet, the first cliffs which were met are composed of beds 

 of coarse sand, or fine gravel, alternating with argillaceous deposits.- 

 At one cliff, about 40 feet high, the gravel, composed of angular frag- 

 ments of trap-rocks, occurred both above and below a coarse slightly 

 cohesive sandstone ; the strata dipping to the S.E. About two miles 

 farther up, the cliffs rose to the height of from 300 to 400 feet, and 

 were composed of a coarse sandy gravel. The pebbles in the bed of 

 the river were now mixed with masses of white sandstone, and of 

 puddingstone or conglomerate, formed by the cementing together of 

 small pebbles by the oxide of iron. Here we found, on the right 

 bank, a stratum of hard blue clay, containing an immense number of 

 marine shells ; Ostrea^ Mytilus, Cardium, Turritella, Cerithium, Te~ 

 rebratula, Ancillaria, Voluta, &c. w^ere in great abundance. The 

 clay-bed was 18 inches thick, lying under a thickness of 20 feet of 

 coarse sandstone, with a dip to the S.E. at an angle of 35°. 



Proceeding along the bed of the river, in which were many spe- 

 cimens of silicified wood, we found this shelly deposit occurring both 

 on the right and on the left banks ; but, although the shells them- 

 selves were identical, there was a remarkable difference in the con- 

 ditions of their imbedding. The shells on the right bank a})pear 

 to have been deposited in blue mud, which has now become, from 

 their decomposition, and by the pressure of the overlying masses of 

 sandstone (in some places 400 feet in thickness), a dense hard blue 

 limestone ; while on the left bank, the shells are deposited in a 



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