250 DE. C. T. TRECHMANN on the [vol. lxxix„ 



or less incomplete sequence of these beds is represented. The 

 intercalation of semi-marine or estuarine plant-bearing sediments 

 among those which carry marine fossils is also an interesting 

 feature, in view of the excellent work which was accomplished by 

 the late Dr. E. A. Newell Arber on these floras. 



I am indebted to Prof. P. Marshall for his company and 

 assistance on several of my excursions in New Zealand, and for 

 providing me with stratigraphical details and a map of the Kawhia 

 and other areas, as also for the loan of specimens. My thanks are 

 also due to Mr. P. G. Morgan, the Director of the Geological 

 Survey of New Zealand, and to Dr. J. Allan Thomson, at one time 

 Palaeontologist to that Survey ; also to Mr. J. A. Bartrum, of the 

 College, Auckland. Several experts at home have kindly assisted 

 me with the fossils : among these are Mr. S. S. Buckman, Dr. 

 P. L. Kitchin. and Dr. L. F. Spath, who has undertaken the 

 description of the ammonites. 



II. The Jurassic Plant -bearing Beds of New Zealand. 



An extremely important monograph has recently appeared,, 

 dealing with the plant-bearing beds of Triassic and Jurassic age. 1 

 As the evidence from the fossil plants does not seem in every case 

 quite to agree with that of the marine faunas, it may be advisable 

 to refer to some of these points. 



The earliest flora, that of Mount Potts, is said to be Rhsetic or 

 Triasso-Rhsetic in age. This result agrees, on the whole, with my 

 determination of the Kaihiku marine fossils that occur at Mount 

 Potts as Ladino-Carnic, and I have dealt with the matter in the 

 paper on the Trias of New Zealand already cited. 



The flora of the Clent Hills in Canterbury Province is also 

 considered to be Rhsetic, although, owing to the absence of certain 

 forms, it may be slightly younger than the Mount Potts flora. 

 The flora that occurs at Mokoia, near Gore in Southland, is put 

 down as Lower Jurassic, though Mr. McKay referred to the beds 

 as Triassic. 



The flora at the Mataura Falls in Southland is said to be Lower 

 rather than Middle Jurassic in age, and slightly younger than that 

 at Mokoia. New Zealand geologists have referred the Mataura 

 Beds to the Upper Oolite. 



The plant-beds, including the fossil forest at Waikawa in the 

 far south-east, are said to be probably of Middle Jurassic age, 

 though Arber remarks that our knowledge of Upper Jurassic floras 

 is very limited. The stratigraphical position of the beds should, 

 however, refer them to a position high up in the Jurassic. Un- 

 fortunately, I know of no marine fossils associated with either the 

 Mataura or the Waikawa plant-beds such as might confirm or 

 refute these attributions. 



1 E. A. Newell Arber, ' The Earlier Mesozoic Floras of New Zealand ' N.Z. 

 Geol. Surv. Pal. Bull. No. 6, 1917. 



