strata as at Kotá. The slaty limestone abounds with scales of Lepidotus, and the underlying white shale with Estheria. At Sironchá, (Chiranjá) six miles south of Kotá, on the same bank of the Pranhítá, rocks are met with which would seem to be inferior to these. The highest is a coarse sandstone, enclosing pieces of indurated clay, under which lies a very hard fine argillaceous sandstone of various colours, from a dark red to a pale bluish-pink. In the latter my collector, four years ago, discovered compressed stems, which I considered similar to those of Silewádá; and, from the specimens which have since been obligingly sent me by my friends C. R. Glasfurd, Esq., and Dr. Cameron, there can be no doubt of the correctness of the opinion. It is now with me a settled point that the stem-bearing argillaceous sandstone of Sironchá is of Dámúd age, like that at Silewádá. About ten miles a little north of west from Kota is Krishnapuram, near which commences an outcrop of red clay, which continues westward for twelve miles to Bimeni. Máleḍi is surrounded by fields of this red clay; but on the south side, at no great distance, is a rise of whitish sandstone, covered with bushes. Near the foot of this elevation, about a mile west of the village, is the site of the Ceratodus teeth and coprolites, on which Dr. Oldham has cast so much light;* while a quarter mile south of the village have been found pitted and grooved bony plates, and vertebræ which bear a close resemblance to those of the Dicynodont, discovered by Mr. Blanford in his Panchet group. Along with these there occurred separate rami of remarkable jaws thickly set with 4-6 rows of strong short conical teeth. A singular future in these jaws is, that there has worked upon them from the opposite jaw a sharp knife-edge, which in most cases has formed a groove along the jaw, cutting off, in a slanting direction, the crown of the teeth that came in its way. In one instance the knife-edge, instead of excavating the usual groove about the middle of the alveolar ridge, has rubbed against the inner row of teeth, and worn them into a flat vertical section. In the same spot a sharp bone was met with, that might have discharged the functions of the cutting instrument, but whether it really did so, or was the mandible of a Dicynodont, I am not competent to determine. Near Bimeni the soil becomes black; but on the west side of Chakinapali, which is three miles west of Bimeni, there is a low hill, at the foot of which red clay is again seen with sandstone above it. With regard to the position of this clay, it is impossible to speak with any certainty; but I think it may be found to underlie the * Mem. Ind. Geol. Surv., Vol. I., p. 295. ? ichthyolitic argillaceous limestone, and perhaps even the stem-bearing argillaceous sandstone. In a paper read before the London Geological Society in March last, I gave it as my opinion that these strata under the Mahadewa series belonged either to the Upper Trias or Lower Jura,-probably the latter. At that time I had not had an opportunity of becoming acquainted with the marked progress recently made by our Indian Geological Survey, or the elaborate and valuable Memoir of its able Superintendent on the rock-systems of Central India and Bengal.* These advantages having since been enjoyed, I will here briefly state my present view regarding the age of the strata under consideration. The members of the Survey, with an accuracy to which only they can attain, have pointed out various breaks in the sequence of the rocks which have fallen under their observation. To these intervals, however, may be assigned greater lapses of time than the facts warrant. For example among the rocks that have been so admirably worked out by Mr. W. T. Blanford,† the Panchet group is shown to rest unconformably on the Dámúdá group; and yet the genus Glossopteris, occurs in the Lower Panchets as well as in the Lower Dámúdás. Again, the Lower Panchets, as Mr. Blanford remarks, appear to be the equivalents of our Mángali argillaceous sandstone, for the Panchet Estheria is evidently the smaller form of the Mángali one, or, as I would prefer expressing it, the smaller of our two Mángali species. Now the Mángali strata, in common with the Kámpti boulders, afford those paper-kitelike fossils which Dr. Oldham considers the detached scales of cycadaceous cones, and which he says are to be met with both in the Rájmahal beds, and those designated Upper Dámúdá by Mr. Medlicott. But what seems to me to carry the greatest weight of all is this, that in the Kámpti boulders species of Glossopteris, which are identified by Sir C. Bunbury with others in the admitted Lower Dámúdá of Silewádá, are embedded along with a species of Taniopteris, which, as far as I can judge, differs very little, if at all, from T. lata (Morris) from Rájmahal. In my opinion, therefore, a shorter period elapsed between the deposit of the Lower Dámádá and the Rájmahal strata than some may suppose. On this point I possess little or no stratigraphical evidence. But perhaps the following statement of Mr. Wall's may have some bearing on it. Speaking of certain mottled clays in the Godavery, below Ma * Mem. Ind. Geol. Surv., Vol. II., p. 299. + Beng. As. Journ., p. 352, Vol. 1860. Mem. Ind. Geol. Surv. Vol. III. pt. 1. are hadeopur, he says that they occur again at Sironchá, where they the immediate underliers of the limestone."* Now the limestone is most probably of Liassic age; and, as the mottled clays of Sironchá, which I have shown to belong to the Dámúdá group, are stated to be its immediate underliers, it is not likely that these are older than the Upper Trias, unless there is a very great hiatus between the limestone and them. The same conclusion is suggested by the relation of the Panchet and Dámúdá groups at Rániganj itself. If the Panchet and Kotá Estheria are to be looked on as nearly allied, or if the abundance of this genus of Entomostraca is to be received in India as indicative of a particular geological horizon, then the Lower Panchets must be reckoned as nearly contemporaneous with the Kotá limestone; in other words, somewhere about the age of the Lias; and if so, the underlying Dámúdá group of Bengal is probably about the age of the Upper Trias. The position of the Máleḍi red clay is at present undetermined; but the borings of Dr. Bell and Mr. Wall would seem to favour the presumption that it is inferior to both the argillaceous limestone and mottled clays of the Pranhítá, which well agrees with the Triassic facies of its fossils. The probability Nothing has yet been done to illustrate the numerous tracks on the Korhádi shale. But I would here desire to recall a statement made by me at a meeting of the Bombay Asiatic Society in November 1858, to the effect that it was probably of marine origin.† lies rather on the side of its deposition in freshwater. rence at Korhadi in a very disturbed area, it is difficult to compare it with other strata ; but from the character of its tracks, and the metamorphic boulders believed to be embedded among its laminæ of fine clay, the authors of the Report on the Tálchír Coal-field appear to be correct in referring it to their Tálchír group.‡ Nagpur, 24th October 1861. Mem. Ind. Geol. Surv., Vol. I., p. 76. *Madras Journ. Lit. and Sc. 1857. + See "Appendix," p. lx.-Ed. NOTE. All the bones found at Nárayanpur and sent to the Bombay Asiatic Society are infiltrated with silex, chiefly in the form of agate and calcedony; this fills the cancellated cavities; while the intervening portions or bony structure, which still presents the lacunæ or bone-cells, and their filamentous expansions or canaliculi together with the Haversian canals into which the latter open, remains calcareous and of a brown or white colour. There are in all, eight of these bones, of which three only have a determinable form; two are the ends of long-bones with their epiphyses or ends dropt off; and the rest are mere fragments of the cancellated structure of large-bones. All the determinable forms belong to the vertebral column and consist of:1st. The transverse processes (with their tips broken off) enclosing the hole for the vertebral artery, the condyloid cavity and part of the body,-of an atlas of some large animal apparently closely allied to, if not an Elephant. The portion is eight inches long from the top of one of the transverse processes to the end of the body, and the condyloid cavity exceeds four inches in its longest diameter. The latter is of the same diameter as that of an atlas belonging to a skeleton of a large specimen of recent Asiatic Elephant in the Grant Medical College Museum, and the extreme length of the fossil bone, if doubled, would exceed the transverse diameter of this atlas; but the hole in the transverse processes for the vertebral artery, the condyloid cavity, and the body being all in one line, (that is, a straight line drawn from the middle of the former to the middle of the latter,would pass through the middle of the long diameter of the condyloid cavity), makes this bone different from any of the atlases of Elephants figured in the "Fauna Antiqua Sivalensis," and different from that of the existing Asiatic Elephant. The second hole or part, of the course for the vertebral artery, is not present. On account of the silicious nature of the infiltration, I cannot make a good section for microscopic examination. 2nd. The body and a small portion of the transverse processes of, a vertebra slightly cenvexo-concave; expanded laterally, so as to be very nearly as broad as its length, which, from the centre of the concave, to the centre of the convex end is 3 inches; vertical diameter of concavity and convexity the same, viz. 2 inches, respectively, and breadth in the centre 2 inches; vertebral canal 13 inch wide. Transverse processes arising from the greater part of the dorsal aspect of the body on a level with the vertebral canal, and extending nearer to the convex, than to the concave end; presenting at their base, at each end, a concave facet in the body of the vertebra apparently for the articulation of a rib.-This vertebra from the depressions for the ribs, its general dimensions, and the microscopical examination, probably belonged to a mammal larger than a Camel, for it is a little longer and much broader than any dorsal vertebra of this animal, and, of course, larger than any of a Horse, Ox, &c. 3rd. The body and a small portion of the transverse processes of a vertebra strongly convexo-concave; compressed laterally; grooved ventrally. Length from the centre of the concave, to the centre of the convex end 3 inches; breadth transversely, in the centre 1 inch; vertical diameter of concavity 27 inches, breadth in the centre 17 inches; vertical diameter of the convexity 2 inches, which is less than that of the concavity; the deficiency being ventral where it appears to have been worn upon, (by another bone?) Vertebral canal inch wide opposite the middle of the transverse processes, which are confined almost entirely to the concave half of the body, and arise from its dorsal aspect, on a level with the vertebral canal. This vertebra probably belonged to a reptile, on account of its strong convexo-concave body which could only be confounded with a cervical vertebra of a mammal; from which again it is distinguished by the absence of the transverse processes in the body of the bone, and therefore the want of the canal for the vertebral artery; while the deficiency in the convexity ventrally, appears to have been for the attachment of the inferior spinous process, which would thus make it a caudal bone. It is a fac-simile of a sketch of a vertebra found at Phisdúra, which Mr. Hislop has sent me for comparison, only that his is of an inch longer. I cannot depend upon the microscopic test here, but the structure tends to a reptilian form; nor is this test worth much generally, so far as my observation extends. There is too little difference between the bone-cells of Mammals and Reptiles to enable one to pronounce immediately, which is which; and therefore, the microscopic test becomes of very little practical value. The Museum of the Bombay Asiatic Society contains very few other recognisable fossil-bones of Crocodiles, and these are almost all from Perim Island opposite the mouth of the Nurbudda river. They consist of imperfect vertebræ, and the anterior ends of lower-jaws, all of which belonged to animals of moderate size. But there is one portion, viz. the anterior part of the upper-jaw of a Crocodile which came from the Bone-bed of Sind, and was presented to the Society by Sir Bartle Frere,of very large dimensions. This fragment, which presents an expanded snout, measures 14 inches from the anterior extremity backwards along the mesial line, and has nine teeth divided by two large notches, one anteriorly and the other posteriorly, on each side of the jaw. It is the same breadth opposite the canines or most expanded portion as at the posterior part, viz. 8 inches. The transverse palatal suture is 10 inches on the mesial line, from the anterior extremity, but extends forward from this to the posterior notch between the teeth on each side, where it is only 7 inches from the middle of the anterior extremity, of the jaw; and the nasal aperture, which is ovate constricted, is 6 inches long by 3 broad in its widest portion. Following the dental margin of the jaw, we find in front, two great teeth, cach 1} inch in diameter, at the alveolar socket, situated close together; then a large notch on each side with conical depressions for three (four including the notch itself) teeth, which belonged to the lower jaw. After this, on the right side, come two large teeth, the first 14 and the second or canine tooth, 13 inch in diameter. Then the posterior notch, out of the sides of which respectively project two teeth each 1} inch in diameter. After this, in a straight line, four other teeth, respectively, 1 1 and 1 inch in diameter. Judging from the general appearance of this fragment, one would say that, in form, the jaw was between that of the thick-nosed Crocodile and thin-nosed Gavial, more nearly allied to the latter than the former; at any rate it belonged to a very large species which perhaps, might have afforded the vertebræ both of Phisdura and Nárráyanpúr.-H.I.C. |