Gudex. — Succession of Tertiary Beth in Pareora District. 253 



The next bed exposed consists of a white limestone, which breaks into 

 small cubes and flakes similar to those found in the A mini limestone at 

 Weka Pass. This limestone is seen in the bed of the river for more than 

 a quarter of a mile, and is well exposed in a section on the right bank. 

 Its greatest thickness in an exposure is 14 ft., but it may really be as much 

 as 20 ft. Near the top its uniform texture changes, and the rock assumes 

 a speckled appearance, due to the presence of tubes or pipes rilled with 

 grey limestone, similar to that found in the overlying stone. There is no 

 erosion surface or other sign of unconformity, so that the change in the 

 character of the rock was due to a change in the conditions of deposit. 

 Some of the tubes appear to be worm-borings, but most of them are too 

 large for such an origin. 



The dark limestone is 4 ft. 6 in. thick in one section, but its thickness 

 varies. In places it is indistinguishable in colour from the ordinary lime- 

 stone, but it is always softer and more arenaceous, and it contains more 

 fossils. In the first exposure seen on Squire's Farm this limestone is 

 crowded with brachiopods, and sharks' teeth are common in " pockets." 



Fig. 6. — Section across Little River, in Squire's Farm. Distance, about 

 180 yards; direction, S.S.W. - N.N.E. ; dip, 25°. 1. White flaky 

 limestone. 2. Dark limestone. 3. Limestone. 4. Limestone with soft 

 iayers, passing into blue clay. .3. Blue clay. 6. Lowest horizon of 

 upper red sands, with large concretions. 7. Gravels. 



The uppermost layer, about 1 ft. thick, contains frequent specimens of 

 Lima (Plagiostoma) laevigata Hutt. and Pecten huttoni (Park). In many of 

 the fossils, the carbonate of lime is replaced, wholly or partly, by iron 

 oxides. The complete list of fossils collected is as follows : Epitonium 

 lyratum (Zitt.), E. browni (Zitt.), Lima laevigata Hutt.. Pecten huttoni (Park), 

 P. scandula Hutt. (?), Echinus sp., Eupatagus greyi Tate, E. tuberculatum 

 Zitt., Balanus sp., Aetheia gualteri (Morris), Pachymagas eUipticus Thomson, 

 Rhizothyris rhizoida (Hutt.), Liothyrella landonensis Thomson, Lamna huttoni 

 Davis, L. incurva Davis, Oxyrhina grandis Davis, and Kekenodon onomafa 

 Hector (?). 



The ordinary limestone affords a fine example of current-bedding, and 

 this fact, taken in conjunction with the arenaceous nature of the rock and 

 the number of quartz grains seen in a microscopic slide, shows that the 

 deposit was not formed in deep water. The fossils obtained from the 

 ordinary limestone were: Epitonium, lyratum (Zitt.), E. browni (Zitt.), Lima 

 laevigata Hutt., L. paleata Hutt. (?), Pecten huttoni (Park), P. williamsoni 

 Zitt., Atrina zelandica Gray, Eupatagus greyi Tate. Pericosnvus compressus 

 McCoy, Pentacrinus stellatus Hutt., Cidaris spines, Retepora (?), Graphularia 

 sp., Aetheia gualteri (Morris), Liothyrella landonensis Thomson, Terebratu- 

 lina suessi Hutt., Rhizothyris rhizoida (Hutt.), Pachymagas huttoni Thomson, 

 P. parti (Hutt.), and Hemithyris nigricans (Sow.). 



