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refer to these as phosphatic nodules. Our 

 opinion is that the change from pure (Aniuri) 

 to glauconitic (Weka Pass) limestone does not 

 take place throughout the mass of the rock, 

 but interlaminations of glauconitic matter arise 

 and separate pieces of limestone. As the con- 

 ditions that control the depositions become 

 more changed, the interlaminations of glau- 

 conitic matter become larger, and the pure 

 limestone is reduced to nodules which appear 

 like rolled pebbles. A similar lamination is 

 distinct at Milburn and Clarendon. In ad- 

 dition to this, it is evident that the elevation 

 of a foraminiferal limestone and its subsequent 

 erosion followed by depression and deposition 

 of glauconitic limestone in perfect accordance 

 without any intervening strata would necessi- 

 tate extraordinary conditions ; in fact, it is 

 almost impossible to suggest a series of con- 

 ditions that would satisfactorily accomit for 

 such a sequence. In this matter we agree with 

 Hector, McKay, Haast, and Park ; but differ 

 from Hutton. 



2. Relations of Weka Pass Stone to Grey 

 Marls. — Very slight imconformity of Haast, but 

 break between Cretaceous and Miocene of Park. 

 No junction is described by either of these 

 observers. We found one below the limestone 

 gorge of the Waipara, as described by McKay, 

 and found a perfect conformity. This is 

 accentuated at the Amuri Bluff, where the 

 Weka Pass stone is absent, and in an ab- 

 solutely clear sea-cliff the Amuri limestone 

 graduates into the grey marls to such an 

 extent that it is impossible to say where one 

 begins and the other ends. There is another 

 clear section of a similar nature at the mouth 

 of the Jed. The idea of this unconformity was 

 based on the mapping of the district (Trans. 

 N.Z. Inst., vol. 37, 1904, pi. 48 ; but compare 

 with Geol. Rep., 1888, sketch-map opp. p. 30). 

 We believe that the former map is totally 

 misleading, though the latter almost represents 

 the actual outcrops. The statement that " the 

 Weka Pass and Amuri limestone are thrown 

 into folds in which the Tertiaries take no part 

 whatever " we believe to be erroneous. The 

 actual structure is as shown in the accompany- 

 ing nuip and diagrams (figs. 4, 5 ; also sec- 

 tions 2, 3, fig. 6), an anticline pitching sharply 

 to the east and bringing the limestone outcrop 

 on the east of the anticline to the level of the 

 railway. To the north this is succeeded by a 

 syncline pitching east and by another sharp 

 anticline, but east of the railway-line the pitch- 

 ing anticline and syncline radiate from a point 

 near the viaduct, Avhere they die away ; so 

 that further east the north limb of the 



