Ut'Ti.ey .—Tertiary Geology, Wharekuri to Otiakt River. 163 



The limestone (a) becomes glauconitic in its upper 8 ft., and is then 

 capped by (6), a glauconitic calcareous shell-bed 18 in. in thickness and 

 crowded with fossils. The band is concretionary in places, and similar to 

 the beds at the top of the Otiake beds at Trig. Station Z, which is only a 

 short distance from this exposure. From this band the following species 

 were obtained : — 



Ancilla papillata (Tate) 

 Bathytoma sulcata excavata Sut. 

 Corbula canaliculata Hutt. 



kaiparaensis Sut. 



*Crassatellites obesus (A. Ad.) . 



Cucullaea australis (Hutt.) 

 Cytherea chariessa Sut. 

 Dentalium mantelli Zitt. 



solidum Hutt. 



*Divaricella cuniingi (Ad. & Ang.) 



Lima colorata Hutt. 

 Niicula saggitata Sut. 



The coral Balanophyllia hectori T. -Woods and Pachymagas hnttoni 

 Thomson were also identified. The overlying bed (c) is less glauconitic, 

 but is capped by another glauconitic hardened bed (d), and above this the 

 rock passes up into a poorly fossiliferous calcareous mudstone (e). From 

 bed (c) were obtained many of the forms detailed above from bed (b). The 

 following additional species occurred : — 



Pecten beethami Hutt. 



chathamensis Hutt. 



huttoni (Park) 



Placunanomia incisura Hutt. 

 Polinices huttoni Iher. 

 Siphonalia turrita Sut. 



*Tellina glabrella Desh. 

 Teredo heaphyi Zitt. 

 Turritella ambulacrum Sow. 



cavershamensis Harris 



semicoficava Sut. 



Venericardia pseutes Sut. 



Corbula humerosa Hutt. 

 Cucullaea attenuata Hutt. 



Leucosyrinx alta (Harris) 

 *Limopsis aurita (Brocchi). 



River-gravels and silts lie unconformably at the top of the section. 



These fossiliferous beds lie above a limestone, of which about 40 ft. is 

 exposed, and are certainly the equivalent of the Otiake beds at Trig 

 Station Z and at Otekaike School. The beds dip 8° in a direction N. 30° W. 

 Greensands crop out on the right bank of the stream about 12 chains 

 farther up the river, dipping in such a way that they would pass beneath 

 the limestone. They are similar to the greensands described at Whare- 

 kuri, containing in places ferruginous nodules. Traces of lamellibranchs 

 were seen, but none could be identified. The rock is calcareous, and the 

 glauconite in it occurs as foraminiferal casts. Still farther up the stream, 

 at the point where the road crosses the river, intensely dark greensands 

 crop out. These greensands are threaded with ferruginous veins. Farther 

 up the stream the qu.artz-grits occur dipping towards the higher beds. 



IV. General Succession and PaLaeontological Notes. 



The Tertiary rocks in the Waitaki Valley form a conformable sequence. 

 The general succession is similar to that in the Waihao district of South 

 Canterbury. Quartz-grits, often containing coal, are followed by micaceous 

 quartzose greensands with interbedded concretionary bands, usually fossil- 

 iferous ; these are followed by calcareous glauconitic greensands (containing 

 a little microscopic quartz and mica), which are often fossiliferous. In 

 the basin of the Maruwenua River and at Black Point a few fossils have 

 been determined, and these undoubtedly represent an horizon near the 

 base of the greensands — Park's Bortonian. The looser glauconitic green- 

 sands lying above the Bortonian have not proved fossiliferous in the 



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