Art. LVI.—On the Marine Tertiaries of Otago and Canterbury, with Special Reference to the Relations existing between the Pareora and Oamaru Series.

By Professor James Park, M.A.Inst.M.E., M.Inst.M.M., F.G.S., Director Otago University School of Mines.

agreement has yet been arrived at upon a subject which is of supreme scientific and economic importance to the colony.

The chief points of disagreement have mainly centred around the stratigraphical position of the beds which contain the Pareora fauna. The views of different writers have involved so many points of radical disagreement that it has been impossible for students of New Zealand geology to reconcile the differences.

In the hope of throwing some light upon this difficult problem I spent two months of the present year in an extended examination of the typical sections throughout North Otago and Canterbury, beginning at Hampden and ending at Waipara.

As the subject was largely palæontological I made considerable collections of fossils, which, with the exception of the brachiopods, I afterwards named by comparing them with the Tertiary types in the Canterbury Museum, all of which had recently been renamed by Captain Hutton, F.R.S., in accordance with latest nomenclature adopted in Europe.

The brachiopods in my collections were named by Captain Hutton, who kindly supplied the revised names as they appear in his paper on “The Revision of the Tertiary Brachiopoda of New Zealand.” (See p. 474 of this volume.)

Altogether over twelve hundred fossils were examined and named. Without the aid of Captain Hutton this would have been a stupendous task; but the work was rendered comparatively easy through the unrivalled knowledge which he possesses of our Tertiary Mollusca.

Historical.

The name Pareora was first used in 1864 by Sir Julius von Haast^* to designate certain fossiliferous marine beds in the valleys of the Pareora, Opihi, and Otaio Rivers in South Canterbury, as well as the Motanau and Greta beds in North Canterbury. Captain Hutton^† subsequently, in his report on the geology of Marlborough and north-east district of Canterbury, in 1873, introduced the Pareora formation into his table of formations, assigning it at this time to the Upper Miocene. Like Haast, he referred the Motanau and Greta beds to this formation; but afterwards, in 1888, as the result of a more complete knowledge of the fossil contents of the different beds, he divided the Pareora formation into an upper and lower group, the former including the Greta beds, which contained about 66 per cent. of living forms.^‡

The Pareora series of Captain Hutton now comprises

the Kakahu, Pareora River, Waihao Forks, Awamoa, and Hampden beds, all of which, he contends, contain a closely related fauna, of which some 37.5 per cent. are living species.^* The Pareora series of the Geological Survey embraces the Greta, Pareora River, Mount Harris; and Awamoa beds; but excludes the Kakahu, Waihao Forks, and Hampden beds, which are placed below the Oamaru stone.

The present position is therefore as follows: According to Captain Hutton all the beds which contain the characteristic Pareora fauna are of Lower Miocene age, and are believed by him to overlie the Oamaru stone, often unconformably^† According to the Geological Survey the Pareora and Awamoa beds are believed to be of Lower Miocene age, and to overlie the Oamaru stone unconformably; while the Kakahu, Waihao Forks, Black Point, and Hampden beds, also containing a Pareora fauna, are admitted to underlie the Oamaru stone conformably.

General Conclusions.

(1.) That there are two limestones in the Oamaru series where the sequence is complete, separated by the Hutchinson Quarry beds and its associates. The upper limestone is a yellowish-brown calcareous sandstone characterized by such fossils as Meoma crawfordi, Cirsotrema browni, and Pseudamussium huttoni. It is the closing member of the series in Otago, Canterbury, and throughout the North Island. The lower limestone is the well-known Oamaru building-stone, typically developed in the Oamaru district. It is absent in South Otago, Waitaki Valley, Waihao, and Kakahu, but is represented by limestones in the Trelissic basin and Waipara district. A consideration of its distribution in the Oamaru district shows that it gradually decreases in thickness towards the west, dwindling to nothing long before the old shore-line is reached. In other words, it is a deposit formed in comparatively deep, clear water. For the upper limestone I propose to use the name Waitaki Stone, and for the lower Oamaru Stone. The Geological Survey and Captain Hutton, recognising only one limestone in the Oamaru district, have applied the name Oamaru or Ototara Stone indifferently to both the upper and lower limestones, which has naturally led to a good deal of confusion with respect to the relations of the Hutchinson Quarry and associated beds to the Waitaki Stone. Of the geologists who have examined North Otago, Mr. McKay was the only one to recognise two limestones. His view is that the Oamaru building-stone is the closing member of the Oamaru series, and that the Waitaki Stone and underlying

I have used the latter name as the more appropriate of the two. The Mount Brown, Mount Donald, Hutchinson Quarry, and Kakanui River beds all belong to the same horizon.

In the Waipara district the Cretaceous, Lower and Younger Tertiaries are very fully developed, richly fossiliferous, and exposed in many magnificent sections which are easily accessible. The district possesses a combination of favourable conditions not found elsewhere, and for this reason it must be regarded as a classic locality of rare geologic importance.

Distinctive Fauna of Oamaru Series.

Physical Characteristics.

the Mount Brown beds by glauconitic sands, or a band of glauconitic sandstone a few feet thick adhering to the base of the Waitaki Stone, and crowded in places with brachiopods and numerous fine examples of Pseudamussium huttoni, Cirsotrema browni, and more rarely Plagiostoma lævigata.

The calcareous sandstones at Shag Valley, Waikouaiti, and Brighton contain a varied fauna which correlates them with the Mount Brown rather than the Waitaki Stone horizon. At Waikouaiti North Head^* they attain a thickness of over 350 ft., this great expansion of the lower horizon having apparently taken place at the expense of the Oamaru Stone.

At Millburn limestone quarry, south of Lake Waihola, the Mount Brown beds are represented by beds of glauconitic sandstone, which pass upward into a compact limestone^† about 80 ft. thick. It is probable that the upper part of this limestone and the calcareous sandstones which overlie it are the local representatives of the Waitaki Stone.

The compact limestone at Millburn is extremely variable in quality along its horizontal extension both going north and south. Passing northward it becomes intercalated with narrow bands of glauconitic sandstone, and attempts to burn the rock for lime at different points have been unsuccessful through the excess of sandy impurity.

Waihao-Kakahu Beds.

These generally consist of blue sandy clays and soft bluish-green sandstones which often contain thin layers, or detached lens-shaped masses, of hard calcareous sandstone. Near the old shore-line these rocks sometimes consist of loose pebbly shell beds, or of loose sandy beds and blue clays alternating.

The molluscous fauna of this horizon is mainly of a littoral character, and it is not a little singular that it contains a number of recent shells that are not often seen in the overlying Mount Brown beds, and never in the Waitaki Stone. This apparent anomaly is doubtless explained by the circumstance that the whole series was deposited on a sinking shoreline, and consequently, while the gradually deepening sea-floor favoured the existence of coralline and brachiopod life, it caused the local extinction or migration of the littoral life.

Where the old coast-line was flat and shelving, the littoral shells would follow the retreating shores westward; but where the coast-line was bounded by high steep land, as we know was the case for long stretches, the littoral forms would be submerged in uncongenial depths, and compelled to migrate

Conditions of Deposition.

The succession of grits and conglomerates, with coal, clays, and sandstones with a littoral marine fauna, followed by coralline sandstones and limestones, clearly prove that the Oamaru series was formed during a period of slow submergence of the old Tertiary shore-line. The grits, and conglomerates, and fire-clays accumulated on the sea-shore and in estuaries, forming the narrow low-lying beach on which the fringe of coal-vegetation afterwards established itself and flourished. The slow progressive sinking of the land in time submerged the forests and destroyed the vegetation, which became covered with littoral sands and estuarine clays, while the littoral deposits in turn became covered by the coralline accumulations of the deeper seas.

The character of the fauna and the large size of the shells indicate warm conditions of a subtropical sea.

Distribution.

After the deposition of the Waitaki Stone the sinking movement ceased, and there began a period of elevation. The newly formed beds now emerged from the sea, arranged as a narrow marginal fringe or bench which contoured around the bays and headlands of the old Tertiary shore-line. They also stretched far back among the mountains, into inland basins and winding fiords, some of which for length and diversity of form are without a parallel at the present time.

Physical Geology.

From the marginal distribution of the Miocene Tertiaries we gather some interesting information with respect to the physical geography of New Zealand in the Eocene. We learn, in the first place, that the main mountain features had already been determined; and, in the second place, that the old Tertiary fiords and inland basins, before the Miocene submergence, were merely deep valleys of erosion which the sinking of the land enabled the sea to encroach and flood like the submerged valleys forming the fiords of south-west Otago in the present day.

the old Cretaceous shore-line, like the Oamaru series at a later date. Moreover, it occurs in the Trelissic basin and in the Clarence and Awatere Valleys, which must therefore have existed as arms of the sea prior to its deposition.

Basement Rocks.

In the Waipara district, and in several parts of Marl-borough, and in the country between Onekakara, near Hampden, and the Upper Kakanui, the Oamaru series rests on the Waipara formation; elsewhere it lies directly on the older Mesozoic or Palæozoic basement rocks. Thus in the Province of Otago it rests principally upon mica-schist and altered sedimentaries; in Canterbury, upon Lower Mesozoic claystones and sandstones; and in Nelson and Westland, mainly upon schists, quartzites, slates, and other altered sedimentary rocks.

Influence of Basement Rocks.

In the places where the Oamaru series rests upon the older basement rocks its lowest member consists of grits and conglomerates, derived from the erosion of the adjacent country. Coal, too, generally occurs with these rocks—at any rate near the old shore-line; but in the localities where the series rests upon the members of the Waipara formation the grits, conglomerates, and coal are absent. The absence of the grits and conglomerates is doubtless due to the lack of the requisite hard rock in the Waipara series to supply the materials, but the absence of the coal is the result of causes which are not very obvious.

Effects of Differential Elevation.

For the most part, the Oamaru series forms the maritime hills and downs of Otago and Canterbury, and a great part of Marlborough, Nelson, and Westland. It gradually ascends as it proceeds inland, in many places rising to an elevation of between 2,000 ft. and 3,000 ft. in the inland basins and valleys and on the flanks of the foothill ranges. And this feature is not confined to the East Coast alone—it is equally true of the western portion of the Province of Nelson, and of Westland, as the examples given hereafter will show.

In North Otago the Waitaki Stone and its associated rocks ascend the Waitaki Valley a distance of over fifty miles from the sea, ending in the Wharekuri basin, which is only a few square miles in extent, being bounded on all sides by steep mountains. Here the Tertiary beds reach a height of over 2,300 ft. above sea-level.

In the Trelissic basin the Oamaru series rises to a height of 3,200 ft. This basin is somewhat less than four miles square, and surrounded on all sides by steep mountains.

In the Waipara district the same beds form ridges reaching over 1,800 ft. high at their highest parts.

The old Tertiaries at the lower end of the Takaka Valley occur at sea-level, but they rise with the gradient of the valley, and gradually ascend till in a distance of thirty miles they reach Mount Arthur Tableland, 3,600 ft. above the sea, where they are almost horizontal. From the tableland going southward the same beds cling to the western flanks of the main range at elevations varying from 2,000 ft. to 3,000 ft., descending westward towards the sea at Mokihinui and Westport and intermediate places. This mantling fringe of Middle Tertiary marine rocks ascending from sea-level on both coasts affords a measure of the elevation of the land since the beginning of the Pliocene, and, moreover, clearly proves the differential rate of the upward movement

The greatest elevation has in all cases taken place along the main orographical axis of the Island, which is situated closer to the west coast than the east. The differential land-movement being most acute on the west coast introduced unequal stresses, which resulted in extensive faulting of the coal-measures between the sea and the axis of greatest elevation. A notable example of this faulting occurs in the Aorere Valley near Collingwood. On the south side of the river the Tertiaries lie at sea-level, but on the north side they crown the range at an elevation of 1,000 ft., and dip away to the west coast.

Contemporary Volcanic Eruptions.

While the sediments of the Tertiary fringe were accumulating on the littoral of the Miocene seas, volcanic eruptions commenced in the area lying between Moeraki and Oamaru. They were submarine, and took place at points lying some miles to the seaward of the old shore-line, most notably in the areas now known as Ngapara, Waiareka, Oamaru, and Kakanui. These eruptions were not very violent; and it was only at Kakanui, and perhaps at Oamaru, that the ejected materials were piled up so as to form volcanic islands. So far as can be ascertained from the distribution of the matter, the volcanic activity began after the close of the Waihao-Kakahu horizon, and ended before the deposition of the Waitaki Stone began. The main outbursts were apparently confined to the Mount Brown or Hutchinson Quarry period.

There is reason to believe that the volcanic eruptions in the Hauraki Gulf area which produced the tuffs interbedded with the Waitematas were contemporary with those near Oamaru.

Life of Oamaru Series.

At the time of the deposition of the sediments of this formation there lived in the New Zealand seas a zeuglodon

whale (Kekenodon onomata, Hector), a giant penguin (Palæudyptes antarcticus, Huxley), a huge shark (Carcharodon auriculatus, Blainville), a ray (Myliobatis plicatilis, Davis), as well as a large nautilus (Aturia australis, McCoy). In the deeper waters there flourished a great variety of corals, bryzoans, and Foramimfera, and with these many brachiopods, pectens, and echinoderms. In the shallow water and estuaries there lived a great assemblage of molluscs, many of which were remarkable for their large size.

Among the shells, which grew to a great size in these genial Tertiary seas, were the following:—

Ostrea wullerstorfi, Zittel.

Pecten athleta, Zittel.

Pecten beethami, Hutton.

Pecten hutchinsoni, Hutton.

Pseudamussium huttoni, Park.

Plagiostoma lævigata, Hutton.

Cucullæa ponderosa, Hutton.

Cucullæa alta, Hutton.

Crassatellites ampla, Zittel.

Dosinia magna, Hutton.

Cardium patulum, Hutton.

Dentalium giganteum, Hutton.

Pleurotoma hamiltoni, Hutton.

Pleurotomaria tertiaria, McCoy.

Cirsotrema lyrata, Zittel.

Turritella cavershamensis, Harris.

Natica darwini, Hutton.

Age of Oamaru Series.

This formation is ascribed by Captain Hutton^* to the Oligocene period, principally, he says, from the occurrence in it of the Cretaceous genus Holaster, two species of which he has described from the Cobden limestone, near Greymouth.^† The genus Holaster, although Cretaceous, ranges into the Miocene of Europe. Of the remaining genera of Echinodermata recorded by Captain Hutton from the Oamaru series in his catalogue of the Tertiary Mollusca and Echinodermata, all but one or two are represented by living species. According to Zittel all of these genera are Tertiary and Recent with the exception of the genus Cidaris, which ranges from Permian to Recent.

The Pareora series of Captain Hutton contains from 20 to 65 per cent. of living molluscs. The Waihao and Kakahu greensands, and the Hampden clays, according to that writer, contain the same fauna as his Pareora series, which he regards as Miocene.^*

Sir James Hector and Mr. McKay have always maintained, and, I think, rightly, that these beds underlie the Waitaki Stone, so that, even disregarding the position of the typical Pareora for the moment, we are compelled to admit that a Miocene fauna exists below the Waitaki Stone. For this reason I think that the Oamaru series must be referred to the Miocene period, having regard for the large proportion of living species which it contains.

In Europe, where the Tertiary record is complete, it is easy to divide the scale of time into small units each characterized by some peculiar feature of its fauna or flora; but in New Zealand, where the Eocene is absent, and where the oldest Tertiaries contain a purely local fauna of which from 20 to 30 per cent are still living, it is not possible to refer the beds with any degree of accuracy to the finer divisions recognised in the Northern Hemisphere.

Relations of Oamaru Series to Lower Tertiary Beds in the North Island.

I will deal first with the marine Tertiaries in the Waitemata district of Auckland.

The pectens which distinguish the Mount Brown or Hutchinson Quarry horizon of the Oamaru series are also characteristic of the middle division of the Waitemata beds near Auckland, which yielded a number of the types originally described by Zittel.

Among the forms common to the middle division of the Oamaru formation and the Waitemata beds are Pecten fischeri, P. vellicatus, P. polymorphoides, P. williamsom, Pseudamussium huttoni, and Amussium zitteli. A large number of the corals, bryzoans, and Foramimfera found in the Orakei Bay beds are also present in the lower limestone at Kakanui and Teschemaker's, commonly associated with the pectens enumerated above. On the other hand, the brachiopods, which are so plentiful at Kakanui, Hutchinson Quarry, Waitaki Valley, Mount Brown, and some parts of Mount Donald, are practically absent from the Waitematas. This, however, can hardly be regarded as surprising in places so widely separated. Even in the Oamaru and Waipara districts the brachiopods are by no means evenly distributed in the same bed, but mostly occur in colonies, often comprising a vast number of individuals.

This partial distribution in horizontal extension is well seen in the long line of horizontal limestone escarpment on the south side of the Waitaki Valley between Black Point and the Marawhenua, and also along the limestone crests of Mount Donald and Mount Brown, in the Waipara district.

The palæontological evidence seems to be sufficiently strong to connect the middle horizon of the Oamaru series, comprising the Kakanui, Hutchinson Quarry, and Mount Donald beds, with the Orakei Bay beds of the Waitematas of Auckland.

The basement beds or lower division of the Waitematas, as exposed at Cape Rodney, Kawau Island, Motutapu Island, and Papakura, contain a molluscous fauna which includes many of the characteristic fossils of the Waihao' horizon of the Oamaru series. They contain, for example, such characteristic forms as Ostrea wutlerstorfi, Pecten burnetti, P. beethami, Crassatellites ampla, Pseudamussium huttoni, Rhynchonella mgricans, and should, I think, be correlated with the Waihao horizon.

The equivalent of the Waitaki Stone is absent in the Waitemata area, but a calcareous sandstone or limestone makes its appearance further south in the Lower Waikato, Aotea, Raglan, Pirongia, Waipa, Kawhia, Upper and Lower Mokau, where it contains Meoma crawfordi, Cirsotrema browni, Pseudamussium hutton, and Magellania novara, all characteristic of the Oamaru Stone horizon.

The sandstones lying conformably below the Waipa limestone, resting on the coal-measures, contain Cirsotrema browni, Calyptræa calyptræformis, Cassidaria senex, Pseudamussium huttoni, Pecten fischeri, Cucullæa alta, Lucina divaricata, and Dentalium lævis, all of which are found in the Waihao beds above the coal.

Age of Waipara Series:

Sir Julius von Haast^* states that he found the impressions of dicotyledonous plants, including Fagus ninnissiana, Phyllites eucalyptroides, Loranthophyllum dubium, Griselina mytifolia, in the lowest part of this series at Waipara and Malvern Hills.

If these species, and the relations of the plant beds to the saurian beds, have been accurately determined, we have a condition of things resembling that of the Laramic (lignitic) series of the Rocky Mountains in the United States, which is referred by American geologists to the Upper Cretaceous.

Hampden Beach Beds.

Kakanui Valley, Near Maheno.

Behind Clark's mills, on the north side of the Kakanui Valley, nearly opposite Maheno Railway-station, which is about a mile away, there is a long line of steep escarpment crowned by the Oamaru Stone. The beds forming this cliff extend northward to Teschemaker's, and eastward—that is, down the valley—about a mile. The most complete section is exposed about 6 chains below Clark's mills, where the Waiareka tuffs, forming the base of the cliff, are followed by a horizon consisting of grey clays interbedded with coralline limestone, which is in turn overlain by calcareous sandstones intercalated with two sheets or sills of olivine-basalt.

The tuffs contain a few indistinct fossils, and bed No. 7 several minute bivalves and numerous Foramimfera. Beds Nos. 9 and 11, and possibly No. 6, represent the Oamaru Stone proper. The presence of the basalt sill shows that volcanic activity was nearly contemporary with the deposition of the lower part of the Oamaru Stone in the Kakanui area. Elsewhere, both to the north and south, activity appears to have ceased somewhat earlier.

At Clark's mill the Oamaru Stone is interbedded with a bed of clay with white chalky joints. This bed varies from a thickness of 12 ft. behind the mill to a few inches at Teschemaker's, less than a mile distant. West of the latter place it thins out altogether. The basalt sill as seen in the longitudinal section of the escarpment, about 2 chains nearer

the mill than the cross-section shown in fig. 1, has been intruded partly along the plane of the clay-bed. The sill ends abruptly at the westward end. The detached mass of limestone entangled in the basalt tends to show that the calcareous sediments had become partially consolidated before the intrusion of the lava.

Fig 1.

Section Near Clark's Mills, Maheno.

Sea-Coast Near Kakanui Township.

From Kakanui Township northward for some distance the beach is bounded by steep cliffs, and in many places is only accessible at low tide. The Tertiaries which form the cliffs bounding the small bay or indentation between the quarry and Trig. T, a quarter of a mile to the north, are lying comparatively

undisturbed, and contain several horizons crowded with the fossils characteristic of the Oamaru series.

Fig 2.

Longitudinal. Section of Upper Part of Cliff (4 chains below Clark's Mill, Maheno).

Stratigraphy.

In the sea-cliffs a few chains north of the quarry and limekilns there are exposed the Oamaru Stone, and Kakanui or Hutchinson Quarry beds, together with intercalated tuffs and lavas.

The section exposed along the cliff at sea-level, 3 chains north of Kakanui quarry, is shown in fig. 3.

Fig 3.

Section Along Sea-Cliff (3 chains north of Kakanui Quarry).

A few chains further north, the cross-section running from the beach westward to trig. station T is as follows:—

Fig 4.

Cross-Section from Sea to Trig. T.

Awamoa Creek.

Fossils are very scarce in the bluish-green sandstone, in places quite common in the clays, and very abundant in the hard pebbly bands, which vary from a few inches to about 2 ft. thick. At the time of my visit the beach outcrops were sufficiently free from shingle to enable me to ascertain that the fossiliferous horizon was only a few yards wide, the bulk of the fossils being contained in one narrow band of shelly sandstone.

Stratigraphy.

The beds are so obscured by beach shingle and recent alluvium that nothing whatever can be made of their stratigraphical relations to the Oamaru Stone and tuffs in the neighbourhood. This information is, however, supplied by the section of Tertiaries exposed at the rifle-butts north of Cape Wanbrow.

Fossils.

A small collection of fossils from the Awamoa beds contained the following species:—

Cape Oamaru.

Section of Sea-Cliff North of Cape Wanbrow.

Section of Sea-Cliff From Cape Wanbrow Northward.

A. Cape Wanbrow. B. Wanbrow Creek. C. South end of section shown in fig. 5. a. Pillow-form basalt and agglomerates. b. Thin-bedded tuffs; angle of dip, 15° to 17°. c. Band of impure limestone. d. Stratified tuffs. e. Oamaru silts.

At the north end of the first small bay south of Cape Wanbrow there is a fault where the dip suddenly changes to the north-east; but some 13 chains south of the fault the tuffs resume the southerly dip, which is continued till the rifle-butts are reached, where they are followed by the Oamaru building-stone, fossiliferous tuffs, Hutchinson Quarry, and Awamoa beds.

The section from Cape Wanbrow southward to the termination of the sea-cliffs is shown in the following section:—

Fig 7

Section Along Sea-Coast From Cape Wanbrow Southward to Rifle-Butts.

A. Cape Wanbrow. B. Fault; strike nearly N.-S. 1. Tuffs. 2. Oamaru building-stone. 3. Fossiliferous tuff bed. 4. Hutchinson Quarry beds. 5. Awamoa beds.

The section exposed along the sea-cliff from a point about 4 chains north of the rifle-butts to the first headland is remarkably

clear, and of great importance, as it shows the relations of the Oamaru Stone to the Oamaru or Waiareka tuffs and to the Hutchinson Quarry beds. It is as follows:—

Fig 8

Section of Sea-Cliff North of Rifle-Butts.

1. Tuffs. 2. Bed of coralline limestone, 6 ft. 3. Greenish-blue sandstone, 9 ft. 4. Coralline limestone (Oamaru building-stone), 80 ft. 5. Yellowish-green fossiliferous-tuff bed, 12 ft. 6. Hutchinson Quarry beds, consisting of hard rubbly limestone, 7 ft., overlain by greensands, 11 ft. thick. 7. Impure shelly limestone, 3 ft. thick, crowded with Turritella cavershamensis. 8. Fine bluish-green sandstones weathering brown, exposed on beach for a distance of 50 yards. 9. Raised beach, 5 ft. or 6 ft. above high water of spring tides, consisting of beach-shingle mixed with littoral shells all belonging to living species. The most common forms are Mactra discors, Chione oblonga, Dosinia australis, Atactodea subtriangulata, Mytilus edulis, Trochus tiaiatus, &c.

The beds strike N.W.-S.E., and dip S.W. at angles varying from 32° to 35°. The dip of the beds as shown in fig. 8 is somewhat exaggerated, in order to crowd the strata into the width of the page.

In this section the Awamoa and Hutchinson Quarry beds are seen to be part and parcel of the same series, a contention urged on several occasions by Mr. McKay, and now admitted by Captain Hutton.

Both Captain Hutton and Mr. McKay correctly enough place the Hutchinson Quarry beds above the Oamaru building-stone, but the former, failing to recognise the existence of two limestones in North Otago, and believing the Oamaru Stone to be the closing member of the Oamaru series instead of the lower of the two limestones, ascribes the Hutchinson Quarry beds to a period subsequent to the Oamaru series.

From bed No. 8, which I believe to be the equivalent of the Awamoa beds, I collected the following forms:—

The shelly limestone, bed No. 7, underlying the Awamoa sandstones, contains large numbers of Turritella cavershamensis, as well as examples of Scaphella pacifica, Lima paleata, Ostrea angasi, and Flabellum radians.

From the greensands, bed No. 6, which evidently represent the Hutchinson quarry horizon, I collected from the lower part especially Magellania novara, Magellania parki, and Bouchardia elongata.

The yellowish-green tuff bed contains a number of small shells, including representatives of the genera Diplodonta, Venericardia, &c., mostly too minute for identification. Possibly the majority of them are new species.

The Oamaru building-stone is represented by two beds—namely, beds Nos. 2 and 4—which are separated by a thin stratum of dark bluish-green sandstone. These beds are composed principally of comminuted corals and Foraminifera, but the higher part of the upper band contains, besides these, a good many littoral shells, among which I collected the following:—

The higher part of the upper band also contains fragments of volcanic ash. The lower band is quite free from volcanic matter and from large shells, and, being of even texture and colour, furnishes the highest quality of building-stone quarried near Oamaru. The upper band is not so uniform in texture, is variable in colour, often containing streaks of a deep-yellow colour, and is in consequence regarded as of inferior quality.

Teschemaker's.

There are two bands of limestone at this place, separated by a few feet of fossiliferous tuff. They are well exposed in the old quarry near the crown of the hill overlooking the railway-line. The upper limestone is the typical clean pale

yellowish-grey building-stone. The lower is glauconitic, and largely composed of comminuted corals and Foraminifera.

The tuffs are often pebbly, and generally crowded with corals and molluscs. Of the latter I collected the following forms:—

Devil's Bridge.

This place is situated near the source of the Oamaru-Stream. Here the Waitaki Stone overlies glauconitic sand-stones containing fossils in great abundance, and generally well preserved. In the collection from the sandstone the following were identified:—

Pukeuri.

This place lies north of Oamaru, from which it is distant about six miles by rail. The hills facing the railway-line, near Pukeuri, are composed of soft sandstones, which are fossiliferous, and often contain large calcareous nodules. From these beds I collected the following forms in the deep cutting on the main cart-road into the Waitaki Valley:—

Neither the Waitaki Stone nor the Oamaru Stone is present in the vicinity of this place, and some difficulty would be encountered in tracing the stratigraphical relations of the two horizons, on account of the great depth of superficial deposits resting on the hills. The character of the fossils, however, clearly correlates the sandstones with a horizon below the Oamaru Stone.

Hutchinson's Quarry, Oamaru.

The beds exposed near Eden Street Bridge are as follows, in ascending order:—

From beds Nos. 2 and 3 the following species were obtained:—

The fossils and character of the material clearly relate these beds to the fossiliferous tuffs and calcareous beds at Kakanui Beach and Cape Wanbrow.

Black Point, Waitaki Valley.

Stratigraphy.

Mr. McKay^* examined, and afterwards accurately described, the stratigraphy of this place in 1876. The numbers of the Tertiary series in descending order are as follows:—

1.	Waitaki Stone, with 1A adhering to base.
1A.	Glauconitic sandstone, fossiliferous.
2.	Sandstones, often micaceous and gritty.
3.	Rusty-brown sands and sandstone, containing layers of hard calcareous nodules and lensshaped masses.
4.	Fireclays, carbonaceous shales, and brown coal.
5.	Quartz and sandstone conglomerates, often limonitic.

The arrangement and relationships of these beds are shown in fig. 9.

Fig. 9.

Section at Black Point Coal-mine.

Marawhenua.

From the glauconitic greensands at the base of the Waitaki Stone, a mile and a half east of this place, in the cliffs, facing the railway - line, I collected the following forms:—

The fine pecten Pseudamussium huttoni occurs in great numbers, in a fine state of preservation, and easily extracted. The brachiopods occur in thousands. The fossils and stratigraphy clearly correlate these beds with the Mount Brown and Kakanui limestones.