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This bed passes insensibly into a completely tufaceous bed with occasional 

 pillows scattered through it. The tufaceous matter, however, rapidly 

 diminishes, and the rock becomes a pillow-lava, which will be discussed in 

 the sequel. 



(2.) Oamaru Rifle Butts. 



Near the Oamaru Rifle Butts, on the south-west side of Oamaru Cape, a 

 clear section is exposed on the beach. It is interesting, as the pillow-lavas 

 are absent and a bed of limestone nearly 50 ft. thick is followed almost 

 immediately by the Hutchinsonian greensands. A fault occurs immediately 

 north of this section, and just beyond the fault there is a marked strati- 

 graphical break in the tuff - beds, exactly similar to the unconformity 

 described in the tuffs near the breakwater. 



The section extends from a point immediately north of the target sheds 

 to the fault which cuts the tuft's just past the first headland. 



S50°W 



Fig. 2. — Section northwards from Rifle Butts, distance about 160 yards, (a) and (a x ) 

 tuffs ; (6) calcareous fossiliferous tuffs, 1 ft. ; (c) limestone agglomerate, 

 2 J ft. ; (d) (7 ft.) and (d t ) (40 ft.) limestone; (e) fine blue tuffs, 8ft.; 

 (/) greenish calcareous tuffs, 11 ft. ; (</) indurated nodular limestone, 

 4 ft. 4 in. ; (h) brachiopod green sand ; (?) shell-bed, 2 ft. ; (j) blue clav 

 100ft.; (k) raised beach. 



The tuffs (a) and (a t ) are calcareous throughout. From the band (b) 

 I collected the following forms : Turbo sp., Turritella sp., Siphonalia conoidea 

 Zitt., Venericardia purpurata (Desh.), Diplodonta zelandica Gray, Chione meso- 

 desma Reeve (?), Dosinia caerulea Reeve, Mesodesma subtriangulatum (Gray), 

 Siphonium planatum Suter, and Liothyrella oamarutica (Boehm). 



Band (c) is a limestone crowded with subangular pieces of volcanic rock, 

 with occasionally inclusions of a coarsely holocrystalline basic igneous rock. 

 Masses of tuff, broken minerals, and pieces of rounded vesicular basalt 

 occur, one of those being 1 ft. in diameter. The bed (e) is a fine brownish 

 tuff weathering blue, and containing several limestone bands. I obtained 

 the following fossils from one of these bands : *Pyrula sp., *Lima lima (L.), 

 *Pecten sp., and Penacrinus sp. 



Mr. Henry Suter writes in regard to the genus Pyrula, " It is an unex- 

 pected addition to our fauna, and indicates a much warmer sea, the genus 

 living now only in tropical latitudes. It is not found Recent in Australasia, 

 but a species was described in 1888 by Pritchard from the Eocene of Table 

 Cape, Tasmania." 



The thicker bed of limestone (d) resembles the building-stone of the 

 Oamaru district ; it is poor in Mollusca and Brachiopoda, but I collected 

 the following: Siphonium planatum Suter, *Pecten hutchinsoni Hutt., 

 Aetheia gualteri (Morris), and Hemithyris sp. 



Overlying the limestone is a fine light-greenish calcareous tufaceous 

 mud, which is very fossiliferous. The species identified were : * Siphonalia 

 conoidea (Zitt.), *Limopsis zitteli von Ihering, *Pecten delicatulus Hutt.. 

 *Lima angulata Sow., *L. bullata Born, *L. colorata Hutt., * Venericardia 

 purpurata (Desh.), and *Mesodesma australe (Gmel.). 



