152 Transactions. 



depression, which follows the line of the Black Hill -Ben Lomond fault as 

 far as Dansey's Pass, near the watershed between the Kyeburn River and 

 the Otiake and Maruwenua Rivers ; but there are indications that this 

 relatively depressed area beyond Ben Lomond is complex in structure, 

 and not due to simple differential elevation along a single fault-line. 

 Beyond the pass occurs the re-entrant forming the north-east corner of the 

 great Maniototo depression {loc. cit., p. 278). The Kurow block is bounded 

 on the south-west by a conspicuous fault-scarp, which rises abruptly from 

 the fault-angle of the Hawkdun tilted block (loc. cit.,]). 278). \ 



From the description given it will be seeii that the tilted block is bounded 

 on the north-west by a tectonic depression, which in the lower course of the 

 Otekaike River is a graben, and towards Dansey's Pass appears to be a 

 narrow somewhat complex fault-angle or synclinal depression. This depres- 

 sion connects the Waitaki Valley tectonic depression with the Central Otago 

 chain of tectonic depressions {loc. cit., p. 268). The Kurow mountain- 

 chain is an uplifted elongated block, bounded by faults on the north-east 

 and south-west, and separated from the Kakanui block by a narrow 

 probably complex tectonic depression. To the north-west the crest of 

 the range is remarkably even when viewed from the Waitaki Valley, and 

 it slopes gently towards the north-west.- The Waitaki Valley, north-west 

 of the Otekaike River, is a graben ; south-east of this line the river flows 

 for some distance in a fault-angle depression, the depression being bounded 

 on the Canterbury side by the splintered fault-scarp of the South Canter- 

 bury block mountains. 



VI. CONCLUSTON. 



The brachiopods listed above from the limestone at White Rocks all 

 occur in the glauconitic base of the limestone at Maruwenua (Park, 1918, 

 p, 83), with the exception of Terebratella totaraensis Thomson, which is 

 doubtfully identified. Murravia catinuliformis (Tate) occurs in the lime- 

 stone at the " Earthquake," in addition to the brachiopods collected by 

 Park {loc. cit.) at Maruwenua. These brachiopods, with the exception 

 Pachymagas huttoni Thomson, have not been found in rocks below the 

 limestone in North Otago. Eight brachiopods — 



Aetheia gaulteri (Morris) \ Pachymagas ellipticus Thomson 

 Liothyrella landonensis Thomson huttoni Thomson 



Murravia catinuliformis (Tate) 

 Neothyris tapirina (Hutt.) 



Rhizothyris rhizoida (Hutt.) 

 Terebratulina suessi (Hutt.) 



can now be recorded from the body of the limestone in the Waitaki Valley. 

 None of these fossils occurs in Park's so-called Upper Hutchinsonian of 

 the Oamaru coastal district. None of them except Rhizothyris rhizoida 

 (Hutt.) occurs in the " Pachymagas parki " band (Uttle}^ 1916, p. 20) of the 

 coastal district?, which Park would call Lower Hutchinsonian. "fhe writer 

 has found Pachymagas parki (Hutt.), Aetheia gaulteri (Morris), Terebratulina 

 suessi (Hutt.), and Rhizothyris rhizoida (Hutt.) in the greensands between 

 the nodular top of the limestone and the " jmrki " band. Pachymagas 

 ellipticus Thomson, Neothyris tapirina (Hutt.), Liothyrella landonensis Thom- 

 son, and Murravia catinuliformis (Tate) have not been found by the writer 

 above the limestone in the Landon' Creek area. Of these, Neothyris 

 tapirina (Hutt.) and Liothyrella landonensis Thomson are undoubted Oto- 

 taran fossils, and never occur above the Ototaran in the typical Oamaru 

 district. The Hutchinsonian of the Oamaru district has as its highest 

 member a hard glauconitic band crowded with Pachymagas parki (Hvitt.), 

 and usually accompanied with Rhizothyris rhizoida (Hutt.), which Park calls 



