416 Transactions. — Geolotiy. 



He ascertained that volcanic rocks underlie the Ototara lime- 

 stone ; while others, he thought, were associated with the 

 Hutchinson's Quarry beds. He maintained that the Hutchinson's 

 Quarry beds are unconformable to the Ototara limestone, and 

 stated that the fossils prove them to be members of the same 

 formation as the Awamoa beds {Lv., p. 58). Dr. Hector, also, in 

 his Progress Report for the same year, says : " These higher 

 [Hutchinson's Quarry] beds it has been impossible to separate, 

 either stratigraphically or otherwise, from the Awamoa series 

 which overlies them" [I.e., p. ix.). Nevertheless they are always 

 separated in all the classifications of the Geological Survey, the 

 latest of which will be found in the "Reports of Geological 

 Explorations for 1883-4," p. xiii. 



In 1881, Dr. Hector says that the Ototara limestone is 

 separated from the Hutchinson's Quarry beds by a series of 

 volcanic rocks which belong to the upper part of the cretaceo- 

 tertiary ( = Waipara) period." 



In 1882, Mr. A. McKay again visited the district, and 

 extended his observations as far south as IMoeraki.f In his 

 report, the blue clay and dark-green sandstones of Hampden 

 and Otepopo (Moeraki series) are stated to underlie the Ototara 

 limestone : thus returning to the first arrangement of Dr. 

 Hector. 



Last November I re-examined the district, and arrived at 

 the following results: — (1.) Mr. McKay is right in saying that 

 volcanic rocks underlie the Ototara limestone. (2.) He is pro- 

 bably right in his conclusion that an unconformity exists 

 between the Hutchinson's Quarry beds and the Ototara lime- 

 stone, although wrong in the reasons he adduces for it. (3.) 

 He is wrong in his opinion that the rocks of Hampden and 

 Otepopo are older than the Ototara limestone ; and (4.), we are 

 probably all wrong in supposing that any volcanic eruptions 

 took place between the deposition of the Ototara limestone and 

 the Hutchinson's Quarry beds, or during the deposition of the 

 latter. 



Before proceeding to give the evidence on which these con- 

 clusions rest, I wish to remark that my mistake as to the true 

 position of the volcanic rocks at Oamaru arose from supposing 

 that the pieces of limestone found in these rocks were fragments 

 of the Ototara limestone Avhich had been altered by heat ; a 

 defective observation, which led me to assume that the limestones 

 which rest on volcanic rocks at Kakanui and the south-west end 

 of Cape Wanbrow must be younger than the Ototara limestone, 

 and consequently must belong to the Hutchinson's (Juarry beds. 

 I now find that these jiieces of limestone are parts of veins in 

 the volcanic rocks which have been formed after consolidation of 



• " Rep. Geol. Expl.," 1881, p. xxvii. 

 t " Rep. Geol. Expl.," 1883-84, p. 58, etc 



