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figure which is reproduced from that given by Matheron for E. midas.
Beyond this feature and the slightly greater concavity in the outline of the valves, there is the closest resemblance between the Afghan forms and the European.
Locality.-H. 42/582. Shadian, South of Balkh, Afghanistan.
Remarks.-E. plicifera is stated by Coquand to occur in the Coniacian and Santonian, these divisions representing approximately the lower Senonian of more modern writers. The Afghan specimens appear to come from somewhere in the Upper Cretaceous Exogyra limestones.
Exogyra ostracina Lam.
Among the many members of the oyster family from the Exogyra limestone I have been able to find only one specimen, and that an isolated lower valve, which may safely be referred to Exogyra ostracina. This is rather surprising in view of the wide distribution. of this species and its abundance in the South Indian deposits. Whether this rarity is due to the imperfection of the collection under description I am unable to say, but it may be remarked here that the species has not so far been recorded from the Baluchistan Cretaceous.
The length of the valve is 65 mm. and the height 48 mm. The outer or anterior side of the valve is nearly perpendicular, the inner side gently sloping and coated externally with foreign matter to which the animal in life was attached. In consequence of this the external characters of the shell are obscured. It may be observed however, that the beak was strongly and closely incurved, forming more than one complete volution and blending with the valve. The steep anterior side of the shell is rough and irregularly laminated.
The inner side is somewhat prolonged with shelly matter deposited on the object of attachment, but the original outline agreed with the specimens figured by Stoliczka from South India, the posterior margin being nearly straight.
The interior of the valve is well-preserved, and shows a finely crenulated pallial margin.
The muscle scar is a little peculiar, being nearly centrally situated, unusually large and strong, and of somewhat different shape to the published figures of this species. E. ostracina is however admittedly an extremely variable species and this variation is most marked both in the shape and position of the muscle scars,
Pecten (Neithea) quinquecostata Sow.
Locality.-H. 52/547. Near Deh Surkh, Astar-ab valley, south of Sar-i-pul, Afghanistan.
Remarks. This species ranges from the Lower Greensand to the Upper Chalk.
Spondylus calcaratus? Forbes.
Locality.-K. 11/314. End of gorge of the Kamard River, left bank, just above Andao (lat. 35° 20′ long. 67° 53′) Afghanistan, (H. H. H.).
H. 42/556. South-eastern slope of Koh-i-ab-i-shora, south of Shadian, near Balkh, Afghanistan.
Remarks. This species occurs in the Trichinopoly group (Turonian) of South India. As there are no spines or extra prominent primary ribs on the only available specimens, their attribution to S. calcarratus is doubtful and it is possible that they may represent S. truncatus Gold., though the ribbing is a most variable character.
Lima obliquistriata Forbes.
Locality.-K. 11/314. End of the gorge of the Kamard River, left bank, just above Andao, (lat. 35° 20′: long. 67° 53′).
Remarks. This species has been found in the Ariyalur group of South India.
Pholadomya cf. gigantea Sow.
This species is represented by one specimen, a cast in which all the shell structure has unfortunately been destroyed.
The dimensions agree very well with those given by Woods and bring out the most characteristic feature of this species, namely its greatly elongated form. The length appears to be always nearly twice the height. The number of ribs and the other characters of the shell, in so far as they are observable, are in agreement with the published descriptions of this species.
Locality.-K. 11/328. Base of limestone cliff, between Begal and Khárgin dara, Saighan.
Remarks.-In England P. gigantea occurs in beds of Aptian age; in western Europe it is found in the Valenginian Neocomian and Aptian; in German West Africa, from the base of the Neocomian to the top of the Aptian. This Afghan specimen came from the beds just below the Micraster horizon and would appear therefore to occur here at a somewhat higher horizon, possibly the Cenomanian.
This cast of a Cardium appears to be allied to Cardium productum Sow., but the specimen is far too badly preserved for specific determination. As far as observable the characters of this species are present. The ribs were numerous and with the lines of growth seem to have divided the shell surface into a serrated series of rectangles so typical of the Cardiida. Traces of tubercles or spines are still to be seen on the front of the valve.
Locality.-K. 11/314. End of gorge in Kamard River, left bank, just above Andao, (lat. 35° 20′: long. 67° 53′).
Mr. Bion summarized his conclusions as follows:
The fauna is dominated by lamellibranchs, of which the Ostræidæ are by far the most abundant group.
The conditions of deposit must have been those of a comparatively shallow sea, the maximum depth of water being reached during the great Upper Cretaceous transgression. It would appear as if during Upper Cretaceous times, Afghanistan had formed the eastern extremity of the South European province. Such a generalisation may seem premature, based as it is on a very small collection of fossils, nevertheless the similarity to the European fauna is so marked that the inference is perhaps excusable.
Unquestionably the chief feature of interest lies in the strong European affinity of the fauna. Almost without exception the species met with can be matched in Europe, and in no direction. is this similarity more strikingly shown than in the occurrence of the typical Upper Chalk genera Cyphosoma and Micraster.
In all, 13 species have been identified ranging, probably, from the Vectian to the Campanian."
1 Vectian is the term adopted by A. J. Jukes-Browne for the Lower Greensand (Proc. Geol. Assoc., Vol. XII, p. 262, 1891-92).