Vol. 52.] IN YORKSHIRE AND LINCOLNSHIRE. 209 



clayey sequence whose fringe is so conveniently revealed to us in the 

 coast-section at Speeton. Westward and southward, on the other 

 hand, it is very probable that the clays diminish, until the sands of 

 the underlying and overlying horizons unite and become indistin- 

 guishable. 1 



g. The Tealby Limestone (with the Upper Clay and 

 1 Roach'). 



I have not devoted so much time in the field to the strata 

 overlying the Tealby Clay as to those below that horizon, mainly 

 because while their general correlation is readily arrived at, a more 

 detailed comparison is rendered difficult by the still incomplete state 

 of our information regarding the upper division of the Speeton Clay. 

 Sufficient has been done, however, to demonstrate the relationship of 

 these rocks to the rest of the section, and to improve our knowledge 

 of their palaeontology. 



The hard calcareous bands with variable clay partings capping 

 the Tealby Clay, known as the ' Greystone ' or ' Tealby Limestone,' 

 form a prominent feature in the stratigraphy between Caistor and 

 Donnington, but are not definitely recognizable farther northward 

 or southward, nor have any continuous hard beds been revealed 

 at this horizon by the borings east of the Wolds. These facts, 

 together with the thin and irregular character of the courses and 

 the extent to which they are interbedded with, and in places 

 overlain by, shaly or clayey material, suggest that the limestone is 

 merely a locally calcareous modification of the upper portion of the 

 Tealby Clay. It is therefore rather surprising to find how greatly 

 the fauna differs from the known fauna of the Tealby Clay. 



The limestone is best exposed in the numerous shallow pits be- 

 tween Normanby and North Willingham. 2 Fossils are everywhere 

 present, but are not easy to extract ; and there seems to be some 

 difference in the species occurring in the different sections. The 

 belemnites again supply the most definite information. They are 

 frequently abundant, especially in the shaly partings, and are 

 all recognizable as well-known Speeton forms occurring in the ' Zone 

 of Belemnites brunsvicensis' (E), namely, B. brunsvicensis, Stromb., 

 B. speetonensis, Pavl., and B. Jasikowi, Lahus. No other species 

 have been found, and the record of B. lateralis from this horizon 

 by Prof. Judd and the Geological Survey was evidently due to the 

 confusion in the determination mentioned on a previous page. 



Ammonites are rarer, the only serviceable specimens that I have 

 myself discovered being found in the higher pit on the north side of 

 the high road, east of North Willingham. These belong to the large 



1 For the discussion of this point see A. Strahan, ' On the Lincolnshire Car- 

 stone,' Quart. Journ. Geol. Soc. vol. xlii. (1886) p. 491. 



2 In this locality the limestone-bands occasionally enfold phosphatic and 

 pyritous concretions, just as the large limestone-nodules of the ' Compound- 

 Nodule Band,' Dl, of Speeton enclose similar earlier concretions. 



