attribute to them a thickness of about 80 feet. The Geological Survey reckon this an over-estimate, and represent the series as 30 feet thick. The beds occur at the foot of the cliff below Peak, extending seawards on the shore. The shore sections are completely hidden by débris from the oolites, and there is thus very little opportunity to study them. They consist of four beds of sandy micaceous shale, separated by irregular bands of nodules, the latter containing fossils of which Ammonites jurensis is most characteristic. The fauna is a mixed one, part of the fossils, such as Discina reflexa, Venus tenuis, Pecten disciformis, Dentalium elongatum, &c., are upper Lias forms; others are Oolitic. The beds exhibit the last remnants of Liassic life and the first dawning of the Oolitic. THE OOLITES. The Peak Cliffs south of Robin Hood's Bay attain a height of more than 600 feet, and exhibit a magnificent section not only of the Upper Lias Beds but especially those of the Inferior Oolite. The two series are brought into juxtaposition by the great fault, with a downthrow to the south of 400 feet. Near the extreme headland, the Peak Steel, a second fault branches to the eastwards, and between the two is the hard triangular mass of rock of the Ironstone Series already described (see fig. 6). A most instructive method of visiting these sections is to descend the circuitous footpath from the top of the cliffs above Blea Wyke to the Dogger Beds at the base. The path, which descends from a position near the Peak Railway Station, winds down one of the most beautiful and majestic amphitheatres of rocks in the country. The several strata extend in semicircles, and form a section of great interest and no little grandeur; thence along the cliff base to the Peak Steel, and again ascend by the path which is immediately over the line of fault. The LOWER OOLITES are developed between Blea Wyke and Scarborough, the upper beds forming the lower part of the North Cliff, whilst the lowest beds occur at Blea Wyke. The latter offer an admirable section, and it is possible to examine every bed; they are more extensively developed here than elsewhere, and between the *Yorkshire Lias, p. 19. FIG. 6. (i.) BLEA WYKE POINT SECTION. Lower Shale and Sandstone. 1-3 The Doggers. e. Nerinea bed. d. c. Lines of Nodules. 4-6 Ferruginous and Yellow Sandstones. b. Terebratula bed. 7-9 Grey Sandstones and Shales, with Vermetus (ii.) PEAK ALUM QUARRY SECTION. E. Upper Shale and Sandstone. D. L. z. Nodule bed at base. Alum Rock of Upper Lias. x. Leda Ovum bed. y. Line of Ironstone Nodules. bed. base of the Grey Limestone Series and the top of the Upper Lias there is a thickness of nearly 500 feet, whilst at Hawsker the entire thickness is less than 300 feet. The section following is extracted from the memoirs of the Geological Survey (Quarter Sheet, 95 N.W.), and the whole of the series to the base of the Oolites is exhibited in the section : Moor Grit SECTION OF THE CLIFFS AT AND NEAR BLEA WYKE. Massive false-bedded sandstone, resting Ft. Ins. ... 40 0 100 O Grey Limestone (Sandy and calcareous shale, resting on 100 0 8 0 occasional beds of fire clay and a thin ... Thin flaggy sandstone, resting on a few Total 110 O 15 0 150 O 95 0 633 0 The DOGGER receives its name from its weathering into roundish lumps or doggers enclosed in a ferruginous casing. The lowest bed of the Oolites consists usually of reddish ferruginous sandstone, slightly calcareous, and is a littoral formation with numerous nodules. At Blea Wyke it may be seen on the beach rising from the sea level, and the following series of beds may be traced :— SECTION IN DOGGER BEDS AT BLEA WYKE. 1. Dogger sandstone, hard, red, and ferruginous, with small projecting masses of oxide of iron; pebbles scattered throughout 2. Ferruginous band, composed entirely of shells, the lime nearly all replaced by iron; the Nerinara Band... 3. Greenish dogger sandstone with pebbles, scattered and in bands 5. Ft. Ins. 10 0 1 6 ... 25 0 1 4. Ferruginous shaly micaceous bed; very few fossils Brown sandstone, crowded with Terebratula trilineata Soft brown sandstone, becoming yellow in lower parts; fossils in nests, calcareous casts of large alveoli of Belemnites; pebbles scattered throughout 20 2 0 25 0 7. Soft grey sandstone, forming a back to the scar; fossils in nests. Vermetus Bed ... 10 O 8. Soft sandstone and hard grey sandy shale; fossils in nests, fossil wood, Belemnites, &c. 25 0 9. Soft grey sandy shales ... 7 0 10. Soft dark grey shales with doggers; the uppermost dogger band being almost composed of Lingula The Dogger Sandstones (1) is the same as seen in other parts of the district, but the beds (2-9) are not, for the most part, known to occur elsewhere. The Nerinæa band (2) is readily distinguished by its dark red colour, immediately above the doggers, and may be seen rising from the sea level to a height of 15 or 20 feet in the north end of the cliff, it is replete with fossils of undoubtedly Oolitic facies. The following list is recorded in the Memoirs of the Geological Survey (Sh. 95, N.W., p. 27). .— Rhynchonella obsoleta, Sow. Terebratula perovalis, Sow. Hinnites relatus, Goldf. Gervillia tortuosa, Sow. Pteroperna striata, Bean. Opis Phillipsii, D'Orb. Astarte elegans, Sow. Natica adducta, Phill. The Terebratula Bed (5) consists of two feet of soft brown or yellowish sandstone, full of fine casts of Terebratula trilineata, Y. and B., other fossils being small and mostly found in nests. This appears to be the lowest bed found in any other locality, and the remaining strata are unique in this section. Trigonia and other fossils are associated with the Terebratula. At the base of No. 9 is a thin stratum of sandy nodules, almost composed of Lingula Beanii, and known as the "Lingula Band" (10). They are readily observable at the foot of the cliff at its northern extremity at Blea Wyke, and other bands of a similar nature occur lower down. They are the uppermost beds of the Lias. The lower beds are not easy to observe, because they are under water except at unusually low spring tides. From the occurrence of A. striatulus and A. Jurensis in these shales they have been variously named the " A. striatulus beds" and the "A. Jurensis shales." The whole of the Dogger Series thin away very rapidly towards the Peak, and their course is stopped by the great Peak Fault (fig. 6). The ferruginous beds with the characteristic doggers again appears in the Peak Alum Works, from whence its outcrop may be traced to Howedale Beck, after which it is covered by the Boulder Clay. The LOWER ESTUARINE BEDS are of freshwater origin, and at Blea Wyke consist of alternating beds of shale and sandstone, with three beds of thin coal attaining a thickness of 160 feet. A bed of soft ferruginous sandstone occurring at a height of 50 or 60 feet from the base of the series contains vertical stems of plants often five feet in height, which are probably the remains of Equisetites. At the summit of the Lower Estuarine Series is the Eller Beck Bed, so |