252 DR. C. T. TRECHMANN ON THE [vol. lxXlX, 



the very base of the Bastion Series. They consist of dark decom- 

 posed felspathic sandstones, with big concretions. The beds are 

 full of fossils, but only the larger forms are in a condition to make 

 satisfactory determination possible. Species of the ammonite 

 genus Psiloceras occur here, and several species of Oxytoma were 

 found. Small indeterminable mollusca are very plentiful, including 

 species of Pecten, a small concentrically-ribbed Astarte, a small 

 wedge-shaped lamellibranch (possibly a form of Tancreclia), and 

 Naticoid gasteropoda. Fossil drift-wood also occurs in the rock. 

 The ammonites refer the beds to the Hettangian. 



(2) The second locality was some distance up the slope of Flag 

 Hill in beds, apparently those called the ' Plagiostoma ' Beds, 

 numbered 53 in the same section, and indicated as rather above 

 the middle of the Bastion Series. They consist of fine-grained 

 sandstones, several blocks of which are scattered about the grassy 

 slopes, and contain abundant specimens of a bivalve shell that I 

 have named ' Pseudomonotis ' marshalli. This may be the fossil 

 referred to as ' Plagiostoma ' by the geological surveyors. The 

 fossils are all- casts, and the shells are replaced by a rusty material. 

 Several of the smaller forms are specifically indeterminable, among 

 them being a small patellif orm gasteropod. Others include a small, 

 adherent, Gryphcea-YikQ, ostreiform bivalve, and another resembling 

 a Pleuromya. The Rhynchonellids have a ' Callovian ' aspect. 



The Survey report mentions Astarte Beds as occurring at the 

 top of Flag Hill. These may be the equivalents of the beds with 

 Astarte of the group of A. spitiensis at Totara Point, Kawhia ; 

 but, as we did not visit the top of the hill, I cannot be certain 

 about this. 



In still higher beds in the Hokonui district Inoceramus is 

 recorded, although whether this refers to I. haasti or not, I 

 cannot say. 



The South-Eastern Coast of the South Island. 



Following the direction of their strike in the Hokonui Hills, 

 both the Trias and the Jurassic appear on the south-eastern coast 

 of the South Island, where they are continued out to sea. The 

 steeply-dipping Triassic sequence is found from Nugget Point to 

 the southern end of Shaw Bay or Roaring Bay. South and south- 

 west of this the coast is occupied by Jurassic rocks as far as 

 Waikawa, where the fossil forest occurs. The coast south-west of 

 Roaring Bay and about the Catlins River is difficult of access ; 

 but Prof. Marshall has recently visited it, and informs me that he 

 found Inoceramus in a bed which strikes east-south-eastwards to 

 the boat-landing at Catlins, and on the strike of this bed at the 

 coast he found some belemnites. The boat-landing is precisely a 

 mile from the Rhsetic beds of Roaring Bay, and, as the direction 

 is at right angles to the strike and the dip averages 70° to 75° south- 

 westwards, the thickness of the rock separating the localities is 



