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Lower Mesozoic Plant Fossils from Black Jacks, Waitaki River, South Canterbury By Shona Bell, H. J. Harrington and I. C. McKellar, New Zealand Geological Survey [Read before Wellington Branch, May 11, 1950, received by the Editor, June 29, 1955.] Summary In Part I the geology of plant-beds occurring on the north-east bank of the middle Waitaki River is described briefly. In Part II the plant fossils are listed and the following new species are described and figured Chiroptens biloba, C waitakiensis, Languifolium waitakiense Most of the genera are common in Trassic and Jurassic (particularly Rhaetic) floras in other parts of the world. Part I.—Geology By H. J. Harrington and I C. McKellar Little is known about the undermass rocks on either side of the middle Waitaki Valley Marwiek (1935, p. 332) pointed out that the Wharekuri-Otekaike Fault (Text-Fig. 1) makes an abrupt change in the metamorphic rank of the undermass rocks which to the south are schistose greywacke, slate, and subschist. and to the north are much less altered greywacke, argillite. and conglomerate. In sheared and subschistose greywacke at Mt. St. Mary to the south of the fault, Park (1904) collected marme fossils which had been found in river gravels by McKay (1882), and which Trechmann (1918) and Wilckens (1927) considered to be of Ladino-Carnic age In 1948 plant fossils were discovered at Black Jacks, to the north of the fault, 15 miles north-west of Kurow (Text-fig. 1) Similar plant-beds occur at Malvern Hills, Clent Hills and Mt. Potts, in North Canterbury (Speight, 1928. 1938; and Arber. 1917) The fossils were discovered while we were returning to Kurow from the proposed Benmore dam site in the heavy floods of October, 1948, and early in 1949 a day was spent in further collecting and in making a hurried examination of the district The plant-beds, about 350 feet thick, consist of dark-grey argillites and coarse indurated roundstone conglomerates They occur in a spur-end which to the west is flanked by a wide terrace 50 feet above river-level on the north bank of the Waitaki River, and to the north rises from a small tributary followed by a rabbit fence. Many fern pinnae were obtained from an argillite layer 30 feet thick, lying between conglomerates of similar thickness cropping out where the rabbit fence crosses the spur-end, and the remainder of the plant remains were obtained from rare thin layers of argillite in the succeeding 250 feet of alternating thin conglomerate and thicker shale or argillite In the conglomerates the rounded ovoid cobbles are typically 3in to 6in long, but occasional boulders reach 18m they consist of greywaeke and hard siliceous and tuffaceous dark-grey argillite The rocks are crushed and contorted, but they dip mostly between vertical and high angles to the south-west. Locally along the strike to the south-east some of the argillites are almost erushed out between conglomerate layers The crushing is evidence of a strike-fault extending along the stream followed

Text-Fig. 1.—Locality map to show the position of the plant beds at Black Jacks. The complex fault pattern is after Marwick (1935) with some additions and omissions. Text-Fig. 2–View of the ridge from which the fossil plants were collected It contists or beds of crushed argillite alternating with roundstone cobble and boulder conglomerate Collections were made at points marked with an X. Scale is given by the rabbit-proof boundary fence, and by a motor-truck on the terrace, right-centre

by the rabbit-fence and crossing a low col. to Akatarewa Stream and the Waitaki River (Text-fig. 1). The rocks in the block to the north-east of the fault are exposed almost continuously in a large stream west of Trig. V (Text-fig. 1). and are more indurated than those to the southwest The succession of greywacke and thin dark argillite in this stream is probably about 10.000 feet thick (Text-fig. 3). but only the upper 2,500 feet of beds were examined in situ No identifiable fossils were found either in situ or in the stream gravels, but we found occasional dark carbonaceous streaks in the argillites and we learned that plant impressions have been found by Ministry of Works survevors in the steep crumbling ridges between Trig. Stations J and V. The succession in the block to the south-west of the fault is exposed in fine sections along the bank of the Waitaki River and in cliffs at the back of the 50-foot terrace. The plantbeds are overlain by a thick bed of argillite (Text fig. 3), which in turn is followed by 4,000 feet of well-defined units of greywacke and argillite. The beds look very promising for fossils, but none were found in our rapid search. Text-Fig. 3.—A provisional columnar section showing the stratigraphic position of the plant beds at Black Jacks.

Part II.—Paleobotany By Shona M. Bell (Mrs. Grant-Taylor). Introduction The Black Jacks collections (now in the Geological Survey, Wellington) have been made from different beds at one locality, marked by crosses on Text-Fig. 2 The best impressions were found in a recess under overhanging conglomerate, marked by the third cross from the left. The flora does not show a great variety of species, although in some cases imperfect preservation may mask differences Three new species are described and some additional species are recorded in New Zealand for the first time. The Black Jacks specimens have been compared with the specimens in the Geological Survey Collection described by Arber in 1917. Where such a comparison has been impossible, use has been made of illustrations, although such a method is not always completely adequate. The New Zealand Geological Survey paleobotanical collection number B42 has been given to the impressions, and each specimen has been allocated a serial decimal number. It has been impossible in drawing the veins to maintain an accurate representation of size; most of them have been drawn too thickly. The material is unsatisfactory for photography. List of Fossil Plants B42. Hewlings Survey District, S117/50, Black Jacks, Waitaki River. Cladophlebis australis (Morris) Seward. Chiropteris biloba Bell, n.sp. Chiropteris waitakiensis Bell, n.sp. Thinnfeldia odontopteroides (Morris) ? Thinnfeldia sp. ? Callipteridium sp. Linguifolium lillieanum Arber. Linguifolium waitakiense Bell n.sp. Corystospermaceae, gen. et sp. indet. Ginkgo digitata (Brongn) Heer. Carpolithus sp. Age and Relationships of the Flora All the genera listed above are found in other parts of the world, and most are among the commonest elements in Triassic and Jurassic Floras. Most are typical of the Rhaetic, and occur also in beds of Rhaetic age in Australia, South Africa and South America. As in other early Mesozoic rocks of the Southern Hemisphere, both Cladophlebis australis and Thinnfeldia lancifolia occur abundantly. The genus Linguifolium is also plentiful. It is found as late as the Jurassic. Chiropteris, a plant of doubtful affinities, has been recorded from Asia in rocks of Permian age, but is typical of the Rhaetic in other parts of the world. Calliptcridium has been described from Permian and Triassic rocks in Europe and South Africa. Ginkgo digitata, a variable species of Jurassic age, represents the Ginkgoales From the few impressions present it appears that the Ginkgoales were not as

common in New Zealand as in other parts of the world in Jurassic times. There are no members of the Cycadales or Coniferales in the flora. As well as the species described, there are a number of indeterminable fragments and impressions. Systematics Filicales The ferns are represented by the family Osmundaceac and probably either the Matoniaceae or the Dipteridaceae, to which Ruhle von Lilienstern thinks Chiropteris rightly belongs. Family Osmundaceae Genus Cladophlebis Brongniart Cladophlebis australis (Morris) Seward Text-Fig. 4. Fig. 1. For synonymy see Arber (1917, p. 29). Description. In the specimen figured, the pinna is set obliquely to the raclus. Pinnules alternate or sub-opposite, small, slightly falcate; apex acute; margin entire, attached by the whole base to rachis Midrib well defined; lateral veins once dichotomized. Rachis winged between pinnules. Remarks There are numerous pinnae of this species showing the pinnules and venation very clearly The size of the pinnules varies in different specimens, but there is a tendency for all to be slightly falcate No fertile fronds are associated. Previous records of this species in New Zealand are from Mt. Potts, Clent Hills, Hokonui Hills, Catlins River, Malvern Hills, Mataura Falls, Waikawa, and Waikato Heads, and have been classed as either Rhaetic or Jurassic. C. australis is also present in South Africa, Australia and South America. This is Cladophlebis australis as defined by Morris, not C. patagonica as proposed by Frenguelli for specimens from Waikato Heads and Catlins River, described by Arber (1917). Family Matoniaceae or Dipteridaceae Genus Chiropteris Kurr There are two species representing this genus One of the specimens, although incompletely preserved, is of considerable size. Chiropteris biloba Bell n. sp. Text-Fig. 4, Figs. 11, 12. Description Leaf cuneate, delicate, greater than 4 cm in length and 3.5 cm in breadth, deeply incised into two distinct segments, with lobed distal margin: veins fine, of equal size, closely spaced, spreading from the base, dichotomously forked and frequently anastomosing. Remarks There is one almost complete specimen, and several fragments, which all exhibit the same characteristics One fragment (Text-Fig. 4. Fig. 12) shows the margin particularly well These impressions differ both in shape and venation from C. locerata Arber already described from New Zealand, and do not resemble any other species of this genus already described and figured. In regions other than Asia this genus is found in Rhaetic and Liassic rocks, whereas in Japan. Korea and China it is unknown in the rich floras of this age, but has been found in Permian beds. It has therefore been suggested by Konno (1939) that “Chiropteris must have first appeared in Eastern Asia, and after reaching its highest development there at the age corresponding to the Kobosan Series in Korea, migrated to Europe, South Africa, etc.”

Text-Fig. 4.—Fig. 1—Cladophlebis australis (Morris) Seward, B42.1 X ¾. Fig. 2— Callipteridium sp., B42.10 X ¾. Fig. 3—Thinnfeldia odontopteroides (Morris), B42.7 X ¾. Fig. 4—Thinnfeldia lancifolia (Morris), B42.8 X ¾. Fig. 5—? Thinnfeldia sp., B42.9 X ¾ Fig. 6—Linguifolium waitakiense Bell n. sp., B42.13 X ¾. Fig. 7—Linguifolium waitakiense Bell n. sp, B42.14 X ¾. Fig. 8—Linguifohum lillieanum Arber, B42.12 X ¾. Fig. 9—Linguifolium lillieanum Arber, B42.11 X ¾. Fig. 10—Chiropteris waitakiensis Bell n. sp., B42.6 X ¾. Fig. 11—Chiropteris biloba Bell n.sp., B42.3 X ¾. Fig. 12—Chiropteris biloba Bell n.sp.; B41.2 X ¾. Fig. 13—Carpolithus sp., B41.18 X ¾. Fig. 14—Chiropteris waitakiensis Bell n.sp., B424 X ¾ Fig. 15—Seeds of Corystospermaceae, B42.15 X ¾. Fig. 16—Ginkgo digitata (Brongn) Hee, B42.16 X ¾.

Chiropteris waitakiensis Bell n.sp. Text-fig. 4. Figs. 10, 14. Description. Leaf cuneate, large, deeply incised into four or more straplike segments by repeated dichotomy; veins of equal size, well marked, spreading from the base, forked and anastomosing, the anastomoses beginning at some distance from the base. Remarks. This species occurs commonly in the Black Jacks flora, and differs considerably from C. biloba in size, manner of segmentation and in greater mtervein area. None of the impressions of these large leaves is complete, but all show a spreading form and division into segments. There does not seem to be a sufficiently close resemblance between this and previously described species of Chiropteris for it to be placed in one of them, but the typical venation and the digitate lamina justify its inclusion in this genus. Pteridospermae Genus Thinnfeldia Ettingshausen Thinnfeldia odontopteroides (Morris). Text-fig. 4, Fig. 3. For synonymy see Arber (1917, p. 50). Description. Frond pinnate, often bifureate, pinnules below as well as above the point of bifurcation, close, alternate or sub-opposite, variable in Size, oval or rhombic. Venation odontopteroid; veins numerous, arising directly from the rachis, repeatedly forking; or a more or less well-marked median nerve may be present. Remarks. This species does not seem to be a common member of the flora. The figured specimen, shows a forked pinna. T. odontopteroides is a characteristic plant of the Triassic rocks of the Southern Hemisphere, occurring in Australia, South Africa, South America, and more rarely in India. Thinnfeldia lancifolia (Morris). Text-Fig. 4, Fig. 4. For synonymy see Arber (1917. p. 49) Description. Frond divided into two pinnae set obliquely to each other. Pinnules varying in form according to their position on the rachis, alternate or sub-opposite, mostly elongate, bluntly lanccolate, decurrent with a distinct midrib Venation alethopteroid, the secondary veins arising at rather an acute angle. Remarks This species is common, and variable in form. Like T. odontopteroides this species also is a Southern Hemisphere plant, recorded from the Molteno Beds of South Africa, the Triassic of Australia, and the Rhaetic of Argentine and Chile. ? Thinnfeldia sp. Text-fig. 4, Fig. 5 Description. Frond bipinnate, rachis stout; pinnules opposite or sub-opposite, slender, attached by whole of base. Margin crenate Venation alethopteroid, midrib well-defined, secondary veins forked. Remarks. There is only one impression of this species. Except for its crenate margin and more slender pinnules it resembles T. lancifolia more closely than any other species. It is provisionally placed in the genus Thinnfeldia

Genus Callipteridium Weiss. ? Callipteridium sp. Text-fig. 4, Fig. 2. Description. Frond bipinnate, rachis stout; pinnae sub-opposite, linear, composed of concrescent pinnules so that the margins of the pinnae are smoothly lobed. Pinnules continued on to the rachis, with curving veins entering these lobings directly from the rachis. Venation of the Sphenopterid rather than the Cladophlebid type. Remarks. One small fragment shows the branching of the pinnae to be sub-opposite, and clearly shows the venation of the concrescent pinnules; another is a portion of a pinna. It does not seem justifiable to attach a specific name to such fragmentary remains. Callipteridium, an Upper Carboniferous and Permian plant, has been described by Seward (1903) and Du Toit (1927) from the Upper Karoo Beds of South Africa. Cycadophyta and Related Genera Genus Linguifolium Arber Linguifolium lillieanum Arber Text-Fig. 4, Figs. 8, 9. 1913. Linguifolium lillieanum Arber, Proc. Roy. Soc. Lond, ser. B, 86:346. Pl. 7 Figs, 1, 4. 1917. Linguifolium lillieanum Arber, N. Z. Geol. Surv. Pal. Bull. 6:38. Pl. 3, Figs. 1.7. 1947. Linguifolium lillieanum Jones and de Jersey, Univ. Queensl. Pap. Geol. 3 (n.s.) (3, 4): 48. Description. Leaves spathulate, up to 9 cm or more in length and 1.7-3 cm across at the greatest width. Margins entire, apex rounded, leaf gradually tapering to an elongate base; midrib well-marked, persisting to the apex. Lateral veins arising at an acute angle to the midrib, arching upwards and then bending to the margin, once or twice forked, about 1 mm apart. Remarks. There is no complete specimen, but several of the fragmentary leaves agree very closely with Arber's description and figures. One small, almost complete leaf, 3 cm in length and 1.2 cm in breadth, undoubtedly belongs to this species. Linguifolium has been recorded from Rhaetic and Lower Jurassic of Australia and South America. Linguifolium waitakiense Bell n. sp. Text-fig. 4, Figs. 6, 7. Description. Leaf delicate, linear-spathulate, up to 1 cm in breadth and greater than 6.2 cm in length, tapering very gradually to the base. Midrib well-marked. Lateral veins arising at a very acute angle, and then bending to run sub-parallel to the margin at the outer edge, dichotomising once or twice before reaching the margin, which is entire. The veins are less than 1 mm apart. Remarks. This species is well represented, but there is no complete leaf. The leaf was apparently very long and slender, and exhibits the characteristic venation of Linguifolium. It does not agree sufficiently in size or shape with any of the previously described species to be placed in any of them. It differs from L. lillieanum in the more acute angles between the veins and midrib, and it is more ribbon-like. One specimen, Text-Fig. 4, Fig. 7, shows anastomoses of two of the veins on one side, and has been included in the species since it otherwise closely resembles the numerous other fragments. The anastomoses may bear out Seward's opinion that Linguifolium is related to Glossopteris.

Gymnospermous Seeds Family Corystospermaceae. Text-fig. 4, Fig. 15. A small fragment of a branched inflorescence, completely coalified, shows no structure and so cannot be assigned to a genus. In general habit it agrees with figures by Thomas (1933) of the female inflorescence of the Corystospermaceae. From a main rachis, branches are given off to the right and left in one plane. The pedicels are short and the cupules recurved. The material is too altered to make preparations to show the structure of the stomata or epidermal cells. Most of the members of the Corystospermaceae described by Thomas were from the Molteno flora of Natal, which is essentially Triassic in character. Ginkgoales Genus Ginkgo Linnaeus Ginkgo digitata (Brongn.) Heer Text-fig. 4, Fig. 16. 1876. Ginkgo huttoni (Brongniart) Heer, Flora Foss Arectica. 4 (1). 40. 1888. Ginkgo multubes Lesquereux. non Heer, Proc. U.S. Nat Mus., 11 31. 1900. Ginkgo digitata huttoni (Sternberg) Seward. Cat Mesoz Plants Brit Mus (Nat. Hist.), Jur. Flora, 1: 259. 1905. Ginkgo huttoni (Sternberg) Heer, Fontaine, In: Ward. U.S. Geol Surv Monogi 48: 170. 1905 Ginkgo huttoni magnifolia Fontaine, U.S. Geol Surv. Monogi 48 170. 1917. Ginkgo digitata Walkom, Queensl. Geol. Surv. Publ 259: 8. 1918. Ginkgo digitata Walkom, Queensl. Geol Surv. Publ. 262 9. 1919. Ginkgo digitata Walkom, Queensl. Geol Surv. Publ. 263: 38. 1927. Ginkgoites digitata Du fort. Ann 8th Afi Mus., 22 (2) 370. 1947. Ginkgo digitata Jones and de Jersey, Univ. Queensl. Pap. Geol 3 (us) (3 4): 57. Description Small leaves with slender petiole, 3.5 cm from outer base to outer margin, which is lobed. Lobes with obtusely rounded edges; edges of the lamina forming an obtuse angle with the petiole Veins spreading, branching dichotomously, 8 or 9 to a space of 5 mm. Remarks. These leaves are incomplete, but agree with descriptions of the extremely variable Ginkgo digitata. This species was apparently not common in the Black Jacks flora. G. digitata is known from many beds of Jurassic age and has a wide geographical range, being recorded from America, South Africa, Australia, etc. Plantae Incertae Sedis Carpolithus sp. Text-fig. 4, Fig. 13. Several small ovate seeds averaging 1.2 cm long, with a somewhat raised central region surrounded by a flat border in which there is carbonaceous material suggesting a fleshy envelope. This seed is similar in appearance to Carpolithus mckayi, but has not been included in that species because its carbonaceous nature obscures structure too much to permit certain identification. References Abber E. A. N., 1913. A Prehminary Note on the Fossil Plants of the Mount Potts Beds. New Zealand. Proc. Roy. Soc. Land., ser. B, 86: 344. —— 1917 The Earlier Mesozoic Floras of New Zealand N. Z. Geol. Sun Pal Bull. 6. Brongniart. A. 1828 Histoire des Vegetaum Fossiles. 1.

Du Toit. A. L., 1927. The Fossil Flora of the Upper Karroo Beds. Ann. 8th. Afr. Mus., 22, (2): 289-420. Heer, O., 1876. Flora Foss. Arctica, 4, (1). Fontaine, W. M., 1905. In: Ward, U.S. Geol Suiv. Monogr. 48: 170 Jones, O. A. and De Jersey, N. J., 1947. The Flora of the Ipswich Coal Mcasmes. Univ Queensl. Pap. Geol. 3 (n.s.) (3). Konno. E., 1939. A new Chiropteris and other Fossil Plants from the Heian System, Korea Jap. J. Geol. Geogr., 16. Leequereux, L., 1888. Proc. U.S. Nat. Mus. 11: 31. McKay, A., 1882. Geology of the Waitaki Valley and Parts of Vincent and Lake Counties N.Z. Geol. Surv. Rep. Geol. Explor 1881, 14: 56-92. Marwick, J., 1935. The Geology of the Wharekuri Basin, Waitaki Valley N.Z. J. Sci. Tech., 16 (6): 321-38. Morris, J., 1845. Fossil Floras: 245. In: Strzelecki's “Physical Description of New South Wales and Van Diemen's Land.” Park, J., 1904 On the Discovery of Permo-Carboniferous Rocks at Mount [St.] Mary. Norch Otago. Trans. N.Z. Inst., 36: 447-53. Seward, A. C., 1900. Cat. Mesoz. Plants in Brit. Mus. (Nat. Hist.). Jur. Flora. P 1. 259 —— 1903. Fossil Floras of the Cape Colony. Ann. 8th. Afr. Mus., 4, (1) Speight, R., 1928. The Geology of the Malvern Hills. Dep. Sci. Ind. Res. Geol. Mem 1 Speight, R., 1938. The Geology of the Mount Somers District. Dep. Sci. Ind. Res. Geol Mem 3. Thomas, H. Hamshaw, 1933. On Some Pteridospermous Plants from the Mesozoic Rocks of South Africa. Phil. Trans. Roy. Soc. Land. sen. B, 222: 193-265. Trechmann. C. T., 1918. The Trias of New Zealand Quart. J. Geol. Soc, 73: 165-246 Walkom, A. B., 1915. Mesozoic Floras of Queensland, Part I. Queensl. Geol. Surv. Publ. 252. —— 1917a. Mesozoic Floras of Queensland, Part I contd. Queensl. Geol. Surv. Publ 257 —— 1917b. Mesozoic Floras of Queensland, Part I concl. Queensl. Geol. Surv. Publ. 259. —— 1918. The Geology of the Lower Mesozoic Rocks of Queensland. Proc. Linn. Soc. N.S.W., 43 (1): 37-115 —— 1919. Mesozoic Floras of Queensland. Parts III and IV. Queensl. Geol. Surv. Publ 263. —— 1925a. Notes on some Tasmanian Mesozoic Plants Part I. Proc. Roy Soc., Tasm. 73-89. —— 1925b. Notes on some Tasmanian Mesozoic Plants Part II. Proc Roy. Soc. Tasm. 63-74. —— 1925c. Fossil Plants from the Naabeen Stage of Hawkesbury Series Proc Linu Soc. N.S.W., 50 (3): 214-224. Wilckens, O., 1927. Contributions to the Palaeontology of the New Zealand Trias. N. Z. Geol Surv Pal. Bull. 12. S. Bell. II J. Harrington. I. C. McKellar, N.Z. Geological Survey, 156 The Terrace. Wellington, C.1.

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Transactions and Proceedings of the Royal Society of New Zealand, Volume 83, 1955-56, Page 663

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Lower Mesozoic Plant Fossils from Black Jacks, Waitaki River, South Canterbury Transactions and Proceedings of the Royal Society of New Zealand, Volume 83, 1955-56, Page 663

Lower Mesozoic Plant Fossils from Black Jacks, Waitaki River, South Canterbury Transactions and Proceedings of the Royal Society of New Zealand, Volume 83, 1955-56, Page 663