part 3] JURASSIC ROCKS OF NEW ZEALAND. 251 



Finally, the plant-beds at Waikato South Heads in Auckland 

 are assigned to the Neocomian. S. H. Cox * refers to the plant- 

 beds as part of the Mataura Series, while beneath them comes the 

 'Putataka Series, consisting of marlstones in which marine fossils 

 were found. Among those identified were Aucella plicata, Jno- 

 ■ceramus haasti, and Belemnites awcMandicus. The specimens 

 of Aucella which Prof. Marshall and Mr. Bartrum collected at 

 this locality are described on p. 267. 



Quite recently, Mr. J. A. Bartrum 3 has published a note based 

 on the examination by Prof. A. C. Seward of a collection of plants 

 which the former collected at Waikato. The most interesting of 

 these is said to be Elatocladus plana (Feistmantel). Mr. Bartrum 

 writes to me that Prof. Seward is now inclined to doubt the 

 Neocomian age of the Port Waikato plant-beds, and, though 

 uncertain as yet, he prefers to think that they are probably older. 



III. Description of Localities of Jurassic Bocks. 



The South Island. 



The Hokonui Hills. 



In my paper dealing with the Trias of New Zealand I indicated 

 roughly the structure of the Hokonui Hills ; they consist of a 

 trough of which only the northern and western sides are exposed. 

 The northern and western fringes are occupied by the steeply- 

 inclined beds of the Trias, while the inner and southern parts of 

 the range are occupied by more or less horizontal Jurassic deposits 

 which overlie them. The district was surveyed in great detail in 

 1877-78 by Mr. S. H. Cox & Mr. A. McKay, 3 and a map and 

 several sections, together with a detailed lithological table of the 

 strata, was ptiblished. Unfortunately, neither drawings nor de- 

 scriptions of the fossils collected during the survey are supplied, 

 and consecmently a precise determination of the age of the beds is 

 precluded. 



Above the Upper Triassic Wairoa Series the following beds occur 

 in ascending order: — Otapiri and Bastion Series, Flag Hill Series, 

 Putataka Series, and Mataura Series. 



In company with Prof. P. Marshall, I collected at the two 

 following localities in the Jurassic rocks of the Hokonuis: — 



(1) At the junction of Taylor's Creek with the Otapiri stream. 

 The beds seem to be those marked No. 48 in the section along 

 the line AB in the Survey report, described as lower cannon- 

 ball sandstone, and as belonging to the top of the Otapiri, or 



1 ' Report on the Waikato District ' N.Z. Geol. Surv. : Rep. Geol. Explor. 

 1877, p. 11. 



2 ' Note on the Port Waikato Mesozoic Flora ' N.Z. Journ. Sci. & Technol. 

 vol. iv (1921) p. 258. 



3 N.Z. Geol. Surv. : Rep. Geol. Explor. 1878, pp. 49-90. 



