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Lepidotus longiceps, Eger.
3.-PRODUCTUS-LIMESTONE (Permian to Carboniferous).
Sigmodus dubius, Waag.
Saurichthys (?) indicus, De Kon.
Gen. non det.
Petalorhynchus indicus, Waag. Xystracanthus gracilis, Waag. major, Waag. giganteus, Waag. Thaumatacanthus blanfordi, Waag.
Mastodonsaurus from N. S. Wales.-In Nature' of December 16th, 1886, is published a note recording the reported occurrence in the Haukesbury group of the Gondwánas of New South Wales of a Mastodonsaurus apparently allied to M. giganteus of the European Muschelkalk and Keuper. This determination (which was made by comparison with a cast of the Stuttgart skull, and is therefore probably correct) is of great interest in respect to the occurrence of an allied member of the genus in the Denwa group.1
The recent observations of Mr. Oldham 2 indicate that the Haukesbury beds are probably separated by an unconformity from the underlying Newcastle group, and that the latter is nearly related in time with the Damuda series (Ranigunj, Bijori, and Barakar groups). The presence in both the Denwa and Haukesbury groups of an allied (or perhaps identical) species of Mastodonsaurus, the restricted vertical distribution of that genus in Europe being borne in mind, suggests very strongly the approximate equivalence of these groups. The Denwa group belongs to a considerably higher horizon than the Damuda series3 (Newcastle group), and the elevation of the Haukesbury beds to the same approximate level would accord with the unconformity between the latter and the Newcastle group.
With regard to the homotaxy of the Indo-Australian Gondwánas with the European succession, it may be observed that the Australian sequence rests on marine beds correlated by Dr. Waagen with the lower carboniferous, and that the three groups below the Newcastle consequently correspond to the upper carboniferous; in which division, according to Mr. Oldham's identifications, may likewise be included the Indian Talchirs and the Victorian Bacchus Marsh beds. This being so, the Newcastle and Damudas might correspond to the permian; the Panchets (which might roughly represent the interval between the Newcastle and Haukesbury) to the lower trias; and the Indian Denwa and Maleri and the Australian Haukesbury and Wianamatta to the middle and upper divisions of the latter.
How closely such an homotaxial sequence corresponds with the European horizons indicated by the Gondwána vertebrates of India has been already noticed by myself; and this correspondence is strengthened by the evidence of the Haukesbury Mastodonsaurus. It is true that a certain discrepancy is introduced by the occurrence in the latter beds of Palæoniscus and Myriolepis, but since one species of the former is found in the European upper trias, there is no reason, especially when we recall the persistence in Australia of Ceratodus, why the latter genus should not also have survived in that country to the same epoch.
1 Supra, p. 68.
2 Supra, Vol. XIX. p p. 40, 46.
3 See table on p. 108 of the 'Manual of the Geology of India.'
• Supra, Vol. XIX. p. 35.
5 Ibid. p. 40, note.
6 Ibid. p. 43.
7 Dr. Waagen in the passage cited followed Dr. Feistmantel's erroneous view of correlating the Bacchus. Marsh with the Hankesbury beds, and of removing the Newcastle from the Damudas, which are regarded as probably permian.
8 Ibid. p. 133.
Note on the Echinoidea of the Cretaceous series of the Lower Narbadá Valley, with remarks upon their Geological age, by PROFESSOR P. MARTIN DUNCAN, F.R.S., &C., November 1886.
CONTENTS.-History of the geological and paleontological researches amongst the Cretaceous rocks of the Bág district - A criticism of the palæontology and geological results given in "The Geology of the Lower Narbada Valley, by P. N. Bose, B.Sc., Lond., F.G. S.," in Memoirs of the Geological Survey of India - Lists of the Echinoidea Deductions Description of New Species and notices of the forms already known Description of Plate. In 1865 my attention was directed to a small collection of Echinodermata, Mollusca, and other fossils in the Museum of the Geological Society of London, which had been presented by Dr. H. Carter, F.R.S. The specimens came from strata near Bág in the Lower Narbadá Valley, and they were collected by Captain Keatinge.
The existence of at least eight European types in the small collection, impressed me very much, as did also their unmistakable Upper Greensand facies. A correspondence with Dr. Carter led to the examination of the fossils from S. E. Arabia, which had been collected by him from strata which he considered to be of the same age as the Indian beds and which presented the same mineralogical characters. The specimens from S. E. Arabia were more numerous than those of the Bág beds, and out of eight species of Echinodermata, seven were recognized as European Upper Greensand forms. The Mollusca, a Brachiopod and a Coral from Bág told the same story of the persistence, with slight variation, into the East, of species such as Salenia scutigera, Pygaster truncatus, Epiaster distinctus, &c., Pecten quadricostatus, Neithia alpina, Rhynchonella depressa and Thamnastraa decipiens. The commonest fossils were referable to Hemiaster Cemomanensis, Cott., and Hemiaster similis, d'Orb. A communication was published in the Quar. Jour. Geol. Soc., 1865, Vol. XXI, page 348, dealing with the collections and asserting the Upper Greensand age of the somewhat widely separated groups of strata.
In 1866 Messrs. Blanford and Wynne made as satisfactory a survey of the Lower Valley of the Narbadá as was possible, without the aid of a perfect geographical map. (Mem. Geol. Sur. Ind. VI, pages (207)—(219), (294)—(302), also Blanford, Geol. Bombay, Rec. Geol. Sur. Ind. Vol. V, pt. 3, p. 82. 1872.)
The Surveyors stated that the Cretaceous strata which had been called the Bág beds, rested in one place unconformably on an outlier of the Upper Gondwána series, and that there was a succession, from below upwards, of sandstone and conglomerate, 20 feet, Nodular limestone, nearly unfossiliferous, 20 feet, Argillaceous limestones, fossiliferous, 10 feet, and Coralline limestone (Bryozoan), 10 to 20 feet.
The beds were described and their relation to the overlying Deccan trap explained; moreover it was discovered that the fossils which had come under my notice had been obtained from the Argillaceous limestone. Blanford accepted the particular geological horizon which I considered the species indicated.
In 1868, the Upper Greensand horizon was recognized from the fossils, which were collected by Mr. Holland and subsequently by Mr. Bauerman, in the area of Sinai (Quar. Jour. Geol. Soc., Vol. 23, read December 1866, page 38 (not noticed in the list of contents) and Quar. Jour. Geol. Soc., Vol. 25, page 44, read December 9, 1868, published in 1869).
Two of the species of Echinoidea which had been noticed at Bág and in S. E. Arabia besides many well known Upper Greensand forms were found in one of the collections from Sinai, and in the second collection no less than 13 out of 24 species were recognized as being members of the strata above the Gault and below the horizon of the White Chalk in N. Africa (Algeria). Eight species were found to be common to the Sinai range and Tih and the Upper Greensands of Europe.
In 1873, the late Ferd. Stoliczka had his great work on the Echinodermata of the Cretaceous rocks of S. India published in the Paleontologia Indica, and it became evident that this interesting series of strata did not contain the commonest species of the Echinoidea of Bág and the Arabian districts. Yet an Upper Greensand horizon was clearly identified in S. India, from the facies of the Corals and some of the mollusca, moreover there were European Cenomanian species present. The remarkable fauna of the three groups of Cretaceous strata in S. India had been the source of much consideration amongst European palæontologists, and there were hopes expressed that a further search for fossils would be made amongst the Cretaceous rocks of the Narbadá Valley, so as to obtain the requisite data for a better comparison of the distant strata.
Stoliczka considered that the strata in S. India represented the European Cenomanian, Turonian and Senonian, to the top of the White Chalk. The Ammonites of the lower divisions gave a Gault facies, but Stoliczka noticed that the species which gave the facies had a great vertical distribution in Europe and were found in both Gault and Cenomanian.
In 1880, Mr. P. N. Bose, B.Sc., Lond., F.G.S., of the Indian Geological Survey, was ordered to proceed to the Lower Narbadá Valley and to pay during his survey special attention to the fossiliferous strata and igneous rocks. Mr. Bose had the advantage of an excellent geographical map, and the results of his survey were published in the Memoirs of the Geological Survey of India, Vol. xxi, pt. I. 1884.
Mr. Bose writes with great modesty, not unflavoured with some critical sharpness, when dealing with his predecessors in the stratigraphical part of his work, and he also most straightforwardly asserts his shortcomings as a paleontologist. He states that his determinations of species were "roughly done," and that he availed himself of the assistance of the most careful palæobotanist Herr Feistmantel.
The lists of species published by Mr. Bose are those of the specimens which he collected; he did not avail himself of the collection made, years before, by Keatinge and which is in the Museum at Calcutta, nor did he include the species which had been described by me in the communication already noticed. But in the lists it will be noticed that Mr. Bose places certain forms "taken on the authority of Dr. Duncan's identification." This is hardly correct, for I did not see Mr. Bose's collection, neither did I identify any species for him. I identified the species he names in the collection of the Geological Society, but that is quite another matter.
The succession of strata belonging to the Cretaceous formation in the Lower Narbadá area is according to Mr. Bose, at the bottom
I. A sandstone, "The Nimar," conglomeratic at the base and fine-grained at the top except where in places an oyster bed is found.
3. The calcareous marl, of Deola and Chirákhán.
4. Coralline-limestone (Bryozoan).
5. Lametas (fresh-water).
He confirms Blanford and Wynne's survey in reference to the conformity of the whole of the marine beds, and states, as they did, that the Lameta freshwater beds rest on the eroded surfaces of the underlying Cretaceous strata, and that the Deccan and Malwa Trap covers the Lametas and the eroded Cretaceous strata.
Mr. Bose found an Oyster bed on the top of the sandstone (page 33), and states that it was about a foot in thickness; it rests quite conformably upon some horizontal, extremely coarse grit stones of insignificant thickness and passes above, equally without break, into the lowest beds of the Upper Cretaceous limestone series (nodular limestone). "The species is near, so far as I can make out, to Ostræa Ley merii, an European Neocomian form." Now it is evident that this doubtful Ostræa is not restricted to the lower strata, for (page 33) it is stated :-" At Ghátiá the oyster bed passes under flesh coloured limestones with Bryozoa and bivalves elsewhere met with in the nodular limestone, as well as with diminutive forms of the Ostræa just described [? mentioned] in much diminished numbers."
Mr. Bose proceeds (page 34):-"It may seem ridiculous to attempt to fix the age of a deposit, with any approach to precision, on the approximate identification of only one fossil and that, too, merely an oyster. But this bivalve is a very characteristic fossil of the deposits under consideration, and if it passes up to the overlying limestone, it does so in considerably diminished numbers, and as a rule in diminutive forms and dies out in the course of deposition." On page 34 it is further stated—“Now the nodular limestone, which contains a well defined marine fauna, will be shown in the next chapter to be on the horizon of the Gault or Albian of the European Cretaceous system. We may, therefore, ascribe the oyster-bearing beds, not without some show of probability, to a lower (neocomian) horizon. The oyster being closely allied to an European neocomian form adds strength to the supposition."
These extracts require no comment from a paleontologist except the suggestion that it is a pity that Mr. Bose did not understand the meaning of " a characteristic species," and that he did lean upon such an infirm support as an Oyster of doubtful identity. Unfortunately Mr. Bose states further on in his memoir that the age of the underlying sandstone is unsettled.
The Nodular-limestone is stated to be of Gault age and the list of species is given (page 37). No fossils of this zone had been examined by any one before Mr. Bose made his interesting collection. The fossils of the Deola and Chirákhán marl, which rests conformably upon the Nodular-limestone, which also is often, according to Mr. Bose, marly in its nature, are numerous, and there are 29 forms which Mr. Bose has distinguished generically and in some instances specifically. He assigns the horizon of the fauna to the Cenomanian "or" to use his expression "at about the same horizon," the Turonian being included.
The Coralline-limestone is said to rest conformably on the Marl, and Mr. Bose notices six forms, two of which he names generically, Ostræa and Rhynchonella, and the others he gives specific names to. This limestone is placed by Mr. Bose on the horizon of the Senonian, and as he compares it with the Arriálur series of S. India, it must be placed high up in the Upper Cretaceous series.