Park. — The Lower Mesozoic Rocks of Neiv Zealand. 379' 



could be referred to the genus Productus. I was therefore 

 compelled to conclude that an error had been made in the de- 

 termination of the genus. 



Before discussing the classification of the Lower Mesozoic 

 rocks in its wider aspect, I shall first detail the sequence 

 and fossil contents of the different beds as we find tliem ex- 

 posed at Shaw Bay and Catlin's River and in the typical 

 Trias sections at Nelson and Upper Rangitata, in order that 

 the facts upon which my subdivisions are based may be placed 

 on record. In my examination of the Nugget Point and Cat- 

 lin's River sections I was accompanied by Mr. A. Hamilton, 

 Director of the Colonial Museum, to whom I was indebted for 

 much valuable assistance in the collection and identification 

 of the fossils. 



Previous Geological Examinations. — The Nugget Point 

 district, so far as I can gather, was first geologically examined 

 in 1869 by Dr. W. Lauder Lmdsay, who classified the rocks 

 in Shaw — that is, Roaiing — Bay as Triassic. Mr. McKay, 

 in 1873, made extensive collections of fossils here for the 

 New Zealand Geological Department, but in his report he 

 does not refer the rocks to any particular age. However, 

 the Dn-ector of the Department, in referring to Mr. McKay's 

 collections in the Sixth Annual Report of the New Zealand 

 Institute, considered that the fossils indicated a range from 

 Jurassic to Upper Carboniferous.'"' The next examination of 

 this district was made in the summer of 1874 by Captain 

 Hutton, P.R.S., who grouped the Shaw Bay beds with his 

 Putataka formation of Lower Jurassic age.f Since that date 

 no further geological examination has been made of this 

 district till the present year, covering an interval of twenty- 

 nine years. 



Kaka Point to Hay's Gap. 



The Trias rocks are well exposed at Kaka Point and many 

 places on the beach before Hay's Gap is reached, but the 

 outcrops are small and so isolated by stretches of sand that 

 no contmuous section can be obtained. For that reason no 

 time was spent in making observations where so much 

 obscurity existed, and where the results could not be other 

 than doubtful and possibly conflicting. 



From the beds of Wiltshire Beach McKay collected what 

 he calls a " spirifer," but from his description it was pro- 

 bably a species of Sjnriferina which I found there associated 

 with Halobia, Bhynchonella, &c.j 



* Trans, and Proc. N.Z. Inst., 1875, p. .564. 

 t " Geology of Otago," 1875, p. 43. 

 + L.c, p. 69. 



