Park. — Age and Relations of New Zealand Coalfields. 409 



page xii., commenting on Mr. McKay's work in the North 

 Cape district, uses the following significant words. He says, 

 " No fossils have yet been found in this stratum " [hydraulic 

 limestones] " where it overlies the formations next to be men- 

 tioned " [i.e., Whangarei limestone and coal greensands] "in 

 the Kawakawa Basin by which their age can be decided. 

 They" [hydraulic limestones] "have been referred to the 

 horizon of the Amuri limestone. If they are the same lime- 

 stone as that mentioned by Mr. McKay as occurring at the 

 sources of the Waitangi and Kaeo Eivers, and which is asso- 

 ciated stratigraphically with sandstones and shale containing 

 Ammonites and Inoceramus, this identification would be justi- 

 fied. Unfortunately, wherever these forms are found the 

 downward sequence does not develop the greensands with coal 

 as at Kawakawa. On the contrary, greensands decomposing 

 to rusty sands, and containing such forms as characterize the 

 cover of the coal at Kawakawa and Hikurangi, and also on 

 the west coast of the South Island, are reported by Mr. 

 McKay to rest on the hydraulic limestone of the Kaeo 

 locality." 



Eeviewing the foregoing, we find that Sir James Hector, 

 Mr. Cox, and Mr. McKay have always maintained (a) that 

 the hydraulic limestone overlies the Whangarei limestone 

 which was acknowledged to overlie the coal-measures of 

 Kawakawa and Hikurangi ; (b) that the hydraulic limestone 

 was the equivalent of the Amuri limestone in the South 

 Island ; and (c) that the Pahi and Kawakawa coal greensands 

 containing a Tertiary fauna were the equivalent of the green- 

 sands with Inoceramus underlying the hydraulic limestone. 



The Amuri limestone is held by the Geological Survey to 

 underlie the Gamaru (Weka Pass) stone conformably ; there- 

 fore with the hydraulic limestone above the Whangarei lime- 

 stone, and its equivalent the Amuri limestone below the 

 Oamaru stone, it was found impossible to correlate the 

 Whangarei limestone with the Gamaru stone. 



The views expressed by myself were [a) that the hy- 

 draulic limestone underlaid the Whangarei limestone, (6) that 

 the latter was the equivalent of the Gamaru stone, (c) that the 

 hydraulic limestone was the equivalent of the Amuri lime- 

 stone, and {d) that the hydraulic limestone overlaid the coal 

 greensands. 



It should be noted, however, that every one, myself in- 

 cluded, expressed some doubt as to the true relations of the 

 hydraulic limestone ; and it may be mentioned that the many 

 discordant views on this important question were principally 

 due to the obscurity of the sections, caused by the disturbed 

 condition of the strata and the difficulty of obtaining a con- 

 tinuous or complete succession of the beds on account of the 



