Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/533

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1870.] SHARP NORTHAMPTONSHIRE OOLITES. 367


and has impressed me, combined with considerations as to other areas, with the possibility that we have here a transitional bed connecting the Upper Lias and Inferior Oolite, equivalent to the similar bed (termed by Dr. Lycett " the cynocephala stage ") of Frocester Hill and the Cotswold district.

I would here acknowledge the consideration and courtesy of Mr. Bass in preserving and presenting me with many fossils found in his pit.

Another good section of these beds is temporarily open on the premises of the County Lunatic Asylum, situated at m, at the eastern outskirt of Northampton, and about a mile and a quarter S.E. of Mr. Bass's pit. This will serve further to illustrate the variable character of these beds.

Section at the Northampton Lunatic Asylum.

ft. in. ft. in.

1. A series of fourteen or fifteen bands, from 4 to 6 inches in thickness, alternately orange sand and ferruginous stone, the latter slightly calcareous, an upper stone-band being very ferruginous 6 6

2. A variable bed, sometimes ferruginous sandstone, passing laterally within a few feet into a limestone, dug for building-purposes, contains coral, Thamnastroea, &c 1 3 to 1 6

3. Hard flaggy ferruginous bed, somewhat calcareous 1 6 to 1 9

4. Calcareous band 0 9

5. Hard ironstone, in four or more bands of unequal and varying thickness, very fossiliferous, especially in the uppermost band 2 0

6. Softer and more arenaceous band, many shells 0 9

7. Rich ironstone, in twelve or more irregular bands, of cellular structure, having ochreous and sometimes argillaceous cores, with wood, and occasionally fossiliferous zones about 6 0

8. Bed in blocks, green-hearted with oxidized surfaces on the planes of bedding and joints about 1 6

9. Flaky ferruginous bed, with argillaceous cores, equivalent to the bed no. 10 in the last section about 1 0

One set of joints in this section have a direction N.W. and S.E. ; and the crevices are frequently filled with a soft white material, which, upon analysis by the recently deceased Dr. Berrill (formerly a student at the School of Mines), was shown to be allied to allophane.

The general coincidence of the lower part of this section with the same portion of the last, classed under E, is observable.

The fossils obtained by Dr. Berrill from this excavation have been courteously presented to me by the representatives of the lamented gentleman, who was cut off in early prime, and in the midst of an active career, by an attack of fever, in December last. A list of these fossils is given in the tables ; but I may notice here the remarkable way in which delicate casts of the tests of Trigonioe, Tancredia axiniformis, and some other small shells have been preserved (showing in the same specimens, perfectly, the exterior sculpture and the internal hinge), also impressions of a fragment of Cidaris Fowleri and of a spine of Cidaris Wrightii, the abundance of Pinna cuneata, and the state of preservation of many of the tests of the shells found.