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Transactions. 



A little north of Orairoa Point, six miles south of Waikato River, 

 the basal sedimentaries disappear under the seaward-dipping beds of the 

 younger-mass, and are not found again north of the Kawa Stream, though 

 they are said to outcrop farther south. 



From the South Head to the Waikawau Stream the Mesozoic beds form 

 locally a prominent strike coast — i.e., the coast follows the strike of the 

 seaward-dipping beds, leaving here and there a promontory of very resistant 

 sandstone beds presenting precipitous bluffs to the fierce attacks of the 

 violent Tasman Sea. 



The Marine Fossiliferous Shales or Belemnite-oeds. 



As stated above, the shale-beds at the Waikato South Head contain 

 marine fossils. Cox (1877, p. 19) reported having obtained the following : 

 " Aucella plicata, Inoceramus haasti, Inoceramus (sp. ind.), Belemnites 

 aucklandicus, Halobia sp., Placunopsis striatula, and other species not 

 determined." 



As the result of many hours of patient search, the writer recently 

 gathered from these shales numbers of belemnites, which are abundant, 

 and eight or ten other fossil species not yet determined, but the majority 

 apparently not previously reported from this locality. All that can be 

 said is that amongst the species found at Waikato Heads shales are 

 brachiopods, pelecypods, and gasteropods.* (See Plate XXI, fig. 1.) 



The Fossil-plant Beds. 



From 2,000 ft. to 3,000 ft. higher up in the conformable sequence 

 occur the beds near Oruarangi Point first collected from by Hochstetter 

 (1867, p. 278). These are alternating sandstones and shales, and contain 

 abundant well-preserved plant-fossils. 



Grey Sandy 

 Limestone 



Sands. 



Fig. 8. — Probable section at Oruarangi Point (near plant-beds). 



Newell Arber (1917, pp. 18, 20) in a recent palaeontological bulletin 

 describes and figures a number of fossil plants from these beds. 



After a careful comparison of the plant-fossils gathered on two visits 

 to these plant-beds, and of others gathered by Mr. J. A. Bartrum from 



* Mr. J. A. Bartrum has informed me since the above was written that he forwarded 

 a selection of the fossils from these beds to Dr. C. T. Trechmann, of Durham, and 

 amongst them the following forms were determined by him (accompanying remarks 

 are those made by Dr. Trechmann) : Area (Parallelodon) egertonianus Stoliczka (found 

 in Spiti shales, India, and in Somaliland) ; Area blandjordiana Stoliczka ; Aucella 

 cf. spitiensis exlensa Holdhaus ; Limea sp. (two) ; Pyrgopolon (?) (? a serpu lid) ; Serpula 

 sp. (the Serpula is rather like Serpula convoluta Goldf. from the Dogger : see Zittel- 

 Eastman, p. 138) ; Trigonia sp. Several other forms, notably lamellibranchs and a 

 serpulid, though generically unidentifiable, furnish additions to the above list. 



