Canterbury and Westland. 271 



5. The last series is overlaid by beds of shales and sandstones, 

 the latter having sometimes a semi-crystalline structure, and being of 

 considerable thickness. 



6. Upon them repose very thick beds of a fine-grained sandstone, 

 which has the peculiarity that its matrix or cementing medium generally 

 decomposes to a white powder. Many years ago, comparing this rock 

 with similar rocks in Europe, I applied to it the name of Kaolin Sand- 

 stone, with which it has a close resemblance, at least in outward 

 appearance. Gradually this rock becomes more argillaceous, and is 

 largely interstratified with shales. 



7. The next horizon is formed of several beds of chocolate-coloured 

 or brick-red slates. They are of various thicknesses, and alternate 

 with greyish, greenish, or purple slates. They are more or less 

 arenaceous, of a very distinct character, and have been traced by me 

 over a great deal of ground in several localities in this province, as 

 well as to the more northern portions of this island. From their 

 lithological character and position, I believe them to be the horizontal 

 equivalent of the cherts and diabasic beds which occupy the same 

 horizon in the Malvern hills and elsewhere. 



These beds are again overlaid by a series of beds consisting of clay 

 slates, often of yellowish or greyish tints, semi-crystalline sandstones, 

 changing into graywacke, shales alternating with bluish gray and 

 greenish sandstones, cherts, and many other varieties of sedimentary 

 rocks too numerous to mention. Comparing these beds with those in 

 Mount Potts — the only locality in this province where, as far as my 

 researches have gone, the fossil brachiopods alluded to occur — we 

 obtain the following results : — The beds 1, 2, 3, and 4 of the Clent 

 Hills series, are here represented by a great thickness of dark shales, 

 often becoming so slaty that they may be termed clay slates, alternating 

 with thinner layers of sandstone, sometimes with a ferruginous or 

 calcareous matrix. 



Amongst these deposits occur a few beds of conglomerate, which 

 fairly may be termed bone beds, as in addition to boulders and pebbles 

 of light coloured slates, they consist of great quantities of well rounded 

 pieces of bones and broken shells. The bones are often of consider- 

 able dimensions. I was able to measure the proximal end of what was 

 probably a humerus which I found to be eight inches across, and some 

 other bones of similar dimensions ; however, the bones, as before 

 observed, were so much rolled, and the cementing medium of such 



