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them cannot be older than Middle Cretaceous, probably not older than Cenomanian.1

Whilst looking through Mr. Griesbach's earlier collections one more specimen was found belonging to the genus Micraster. I have little doubt that it came from the same horizon as the Begal specimens, although it is in an extremely bad state of preservation. The locality given for this specimen is "below Exogyra limestone, Middle Cretaceous, Danda Shikan Pass, North of Saighan." The horizon is therefore probably exactly the same. When Mr. Vredenburg's preliminary identification was made the specimens had not been cleaned, and the ambulacra were filled with marl, hence a specific identification was impossible. Since I have cleaned the test, sufficient evidence is available to show that these Micrasters belong to the low zonal forms of the M. præcursor group of Rowe.2 Measurements.-The three best specimens only have been

measured :

Length
Breadth

Height

40 mm.

35 29

22 39

These measurements serve to show the only anomalous features of the test, namely, that the breadth is in some fully equal to the length. This is a high zonal characteristic, associated as we shall see with many definite low zonal features. In this connection Rowe remarks-"It appears to be beyond doubt that in each zone there are broad varieties of the narrow forms."

44

44

27

44

41

28

It will be seen that the height is small, the test being depressed as in all low zonal forms. There is no appreciable development of rostrum or carina. The nature of the ambulacra and the interporiferous areas agrees very closely with that of forms from the Holaster planus zone of the English Chalk. The ambulacra are deep, trough-shaped, and practically smooth. To the naked eye they are certainly quite smooth, and even with the aid of a lens do not show any definite suturing of the inter-poriferous area. The single ambulacrum is a little more advanced as regards suturing and granulation than is the case with the paired ambulacra. It would appear as if the Afghan Micrasters approximate most nearly

1 Mr. Vredenburg apparently saw only four of the Micrasters from Begal, but there are five in the collection.

2 A. W. Rowe. "An analysis of the Genus Micraster." Q. J. G. S., Vol. LV, pp. 494--547, 1899.

to the passage forms between M. leskei and M. præcursor. The apical disc is excentric anteriorly. The amount of this excentricity is difficult to measure on crushed specimens, but averages about 4 mm. The mouth is very distant from the border, the measurement being made from the bottom of the notch to the anterior margin of the peristome. The distance so measured is about 9 mm.

The labrum is slight, triangular in shape, widest where it joins the plastron, and from there tapering to a point. The tip of the labrum is smooth, and the labral plate covered only by a few granules. The periplastronal area is only very slightly granulated.

Serpula cf. gordialis Schlot.

The only specimen referable to this species consists of rounά smooth tubes, one millimetre in diameter, irregularly entangled so as to form a nodular mass. There can be no doubt of the identity of this specimen with that figured by Stoliczka from Ariyalur, S. India.

Remarks.-S. gordialis is abundant in the uppermost Cretaceous beds of Germany, Northern Austria and France. It seems certain that Stoliczka's view that Sowerby's S. plexus from the English Chalk is identical with S. gordialis, is correct. The specimen here recorded also comes from the upper beds of the Cretaceous.

Locality.-H. 42/592. Upper Cretaceous limestone, Shadian, South of Balkh.

1 Stoliczka. pl. XII, fig. 6.

2 F. Kossmat. Vol. XXX, pl. 10,

Serpula filiformis Sow.

Several blocks of limestone in the collection are covered with the long straggling bundles of tubes so characteristic of this species. I have satisfied myself by direct comparison, of the identity of these specimens with those figured by Stoliczka and Kossmat 2 from the Ariyalur beds of Southern India.

1

Locality.-H. 42/403, H. 42/407. North slope of Zurmust Pass, N.E. of Herat.

H. 42/405. North slope of Band-i-Zurmust, N.E. of Herat.

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Cretaceous Fauna of S. India." Pal. Ind., Vol. 4, ser. VIII, p. 63, "The Cretaceous Deposits of Pondicherri." Rec., Gecl. Surv. Ind., fig. 7.

F

Terebratula sella Sow.

This well-known species is represented by several dozens of specimens from the "Firaiman beds" of Mr. Griesbach.

They were at first regarded as a variety of T. gregaria Sueɛs, but subsequently identified by Sir Henry Hayden as T. sella Sow., an identification with which I am entirely in agreement.1

All the specimens correspond very closely with the true T. sella figured by Davidson,2 rather than with the two other varieties of the species admitted by that author. The specimen from the Isle of Wight which Davidson figured on his Plate VII, fig. 6, fairly represents the Afghan form, there being none with the strongly elevated front shown in fig. 4. The globose variety T. sella var. upwarense Walker is not represented in the collection.

Locality. II. 42/279, H. 42/280. 5 miles N.W. of Firaiman, Khorasan.

Remarks. In England and Western Europe T. sella is a typical fossil of the Aptian, and the Afghan examples come from the same horizon.

Terebratula obesa Sow.

There are two specimens referable to this species. One, (II. 42/590) from Shadian, South of Balkh; the other (K. 11/328) from Cretaceous marls near the base of limestone cliffs between Begal and Khárgin dara, Saighan, (lat. 35° 11′ : long. 67° 29′).

The first is a very peculiar form, very wide at the shoulders and tapering to the anterior margin. I have not found any figured form to correspond and refer it with some hesitation to T. obesa. The second is a typical T. obesa.

Terebratula biplicata Sow.

There are several specimens of this species from the southeastern slope of Koh-i-ah-i-Shora, south of Shadian, near Balkh, Afghanistan. They are all preserved as casts only (H. 42/543). Others are from Yakh Dara, west of Faughan, south-east of Maimana, Afghanistan (H. 42/574).

1 Hayden, op. cit.. p. 34.

..

Davidson, British Fossil Brachiopoda," Vol. 1, plate 7, fig. 6, (1851-55).

Inoceramus balticus. Bohm. 1907.

There are several specimens in the collection belonging to this species, their localities being as follows:-H. 42/466, H. 42/467. Upper Cretaceous, south side of Kelat-i-Nadri, Khorasan. G. 373/2 Lower limestone shales between Mari and Dragal, Kaha Pass, West of Dera Ghazi Khan, (W. T. Blanford).

Mr. Griesbach's specimens are referred to under the name I. cripsi Mant. in his paper 1 "Afghan and Persian Field-Notes." It is clear that they come from the Upper Cretaceous beds, so that the present identification as I. balticus is in agreement with the stratigraphical position of the fossils. I. balticus is characteristic of the Senonian of Europe.

There has been considerable confusion in the use of the specific. name cripsi, which has been applied wrongly to the Senonian form I. balticus. Woods has discussed this question.2

Both the specimens from Kelat-i-Nadri and those from the Kaha pass, W. of Dera Ghazi Khan, correspond with I. balticus and not with I. cripsi. The former is characterised by the much greater length in proportion to the height. The fine specimen of I. cripsiamis figured by Stoliczka 3 from the Ariyalur group of South India (which is of Senonian age), is undoubtedly identical with I. balticus. Bohm. It is a form intermediate in type between figs. 51 and 53 on pages 294 and 295 respectively of Woods' memoir. It will be seen from the footnote on page 296 that Woods was of the opinion that Stoliczka's specimen was really I. balticus and after examination of the type I am quite prepared to endorse this opinion.

Gryphaa vesicularis Lam.

An abundant fossil in the Ariyalur group of South India. It is characteristic of the Campanian beds of Europe and has been found in North America, Algiers, Syria and Asiatic Russia.

Localities.-K. 11/323. Top of the Cretaceous; 4 miles south-east of Dasht-i-Safed, Afghanistan, (lat. 35° 20': long. 67° 56′), (H. H. H.).

K. 11/314. End of gorge of Kamard river, left bank, just above Andao, (lat. 35° 30' long. 67° 53'), (H. H. H.).

1 Rec., Geol, Surv. Ind., Vol. XIX, p. 63.

66

? H. Woods. A Monograph of the Cretaceous Lamellibranchla of England,' Vol. II Pt. VIII, p. 295, (1912).

Pal. Ind., Vol. III, p. 405, pl. XXVII, figs. 1—3, pl. XXVIII, fig. 2.

H. 42/550. Deh Surkh, Astar-ab valley, south of Sar-i-pul, Afghanistan, (C. L. G.).

H. 42/581. Yakh Dara, west of Faighan, south-east of Maimana, Afghanistan.

Exoygra decussata Coq.

This is the most abundant and characteristic fossil of the Exogyra limestone of Afghanistan. It occurs in the greatest abundance in certain beds, and as a general rule the larger inferior valve only is preserved. Owing to the strongly arched, gibbous nature of this valve it is impossible to clean out the matter so as to expose the internal characters, and judging by the published figures, very little is known about them.

A comparison of the specimens with those from the European Campanian forming Plate 7 of Coquand's Monograph shows how closely the Afghan forms resemble the European ones.1

Localities.-H. 42/527. Bajgah Gorge, between Mathar and Bajgah north of Saighan, Afghan Turkistan.

G. 373/2. Kaha Pass, between Mari and Dragal, Dera Ghazi Khan district, Sulaiman Range.

Remarks. Among a few specimens brought back by Dr. Blanford from the Sulaiman Hills are some belonging to this species, and which have evidently come from the same set of beds, namely the Exogyra limestone of Afghanistan. In Europe E. decussata characterises the Campanian. The Afghan specimens and those from the Sulaiman Hills come in all probability, from a similar horizon.

Exogyra plicifera Duj.

The specimens referred to this species are in an excellent state of preservation, and the external and internal characters of both valves are to be seen.

They agree very closely with figures 14, 15, 16, Plate 36 of Coquand, though the Afghan form is more concave posteriorly than the European.

A few remarks are necessary concerning the superior valve. The figure given by Coquand (fig. 18) does not agree with my specimens in that the muscle scar is differently orientated in both. I am at a loss to explain the peculiar position of the muscle in Coquand's

1 H. Coquand Monographie du Genre Ostrea," Terrain Crétacé, Atlas, Pl. VII, figs. 1—17 (1 to 69).

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