30 Transactions. 



in New Zealand, where so many localities exist in which numerous stages 

 are in superposition, the younger on the older. It is, therefore, preferable 

 to choose one or more such localities and base the stage names on these 

 alone, applying priority of nomenclature wherever possible, but not insisting 

 on its rigid application. As, however, I propose to use stage names with 

 the termination " ian,"* on a strict reading of priority it is necessary to con- 

 sider only previous uses of similar names, such as Park's use of " Oaniaruian "' 

 and " Wanganuian." In the selection of the localities the abundance of 

 fossils in the various stages represented must be a leading consideration, 

 in order that correlations may prove possible. Thus, although on the 

 assumption of the conformity of the Amuri limestone and Weka Pass stone 

 the Waipara section offers the most complete sequence of Tertiary rocks 

 known in New Zealand, the paucity of fossils in the Amuri limestone, 

 Weka Pass stone, and grey marls is such that correlations on purely 

 palaeontological grounds would be extremely difficult for stages based on 

 these rocks. 



For the youngest Tertiary stages, apparently unrepresented in the South 

 Island by marine rocks, unless in the Awatere Valley, we naust choose 

 between the rocks of Wanganui and of Hawke's Bay. Both have been 

 used already for names of series or systems, but Wanganui has come to be 

 recognized as the type locality, and on grounds of priority may also be 

 justified as such, since Mantell described the rocks of that district long 

 before Hochstetter obtained younger Tertiary fossils collected by Triphook 

 from the neighbourhood of Napier. For the middle and old Tertiary 

 stages the Oamaru district is indicated alike from priority (Mantell's 

 descriptions), general usage, and abundance of fossils. For still older 

 Tertiary stages, apparently not represented at Oamaru, we must go to 

 the West Coast of the South Island. 



I propose further to consider these localities in the following order — 

 Oamaru, Wanganui, West Coast — and to exhaust the possible stages of 

 each in turn. This is necessary, because probably all the stages found 

 at Oamaru occur also in the West Coast, and some at least may underlie 

 the younger beds at Wanganui as they do in the Awatere district, although 

 in none of these cases are they so suitably developed as their correlatives 

 at Oamaru to form the type occurrences of stages. 



The geographical names at present applied to geological systems involve 

 considerations not only of geographical occurrence, but of conformity and 

 unconformity. Thus the term " Oamaru system " has been used in three 

 distinct senses : — 



(1.) By Hutton for part only of the Tertiary sequence at Oamaru and 

 its correlatives. Hutton excluded the Awamoa beds because of a supposed 

 unconformity and faunal difference between them and the uppermost 

 member of his Oamaru system — viz., the Hutchinson Quarry beds. 



(2.) By Park (1905) for the whole of the Tertiary sequence at Oamaru 

 and its correlatives. Park included the Awamoa beds in his Oamaru system. 



* Abbreviated to " an " where the word from which it is derived ends in "i," and 

 to "n" where it ends in "a." Hybrids between .Maori words and anglicized Latin 

 terminations are doubtless unfortunate, but they can hardly be avoided in view of the 

 retention of the Maori place-names throughout New Zealand. They are less objection- 

 able as technical geological terms than as words in the vernacular, and we find that 

 such terms as " Tahitian," "Fijian," and " Samoan " have been easily enough assimi- 

 lated into our everyday speech. 



