118 James Saunders — Geology of S. Bedfordshire. 



tunnel measured six inches in its longest diameter. The most 

 frequent fossils are Ostrea, Belemnites, and Ammonites. Occasionally 

 the bones of Ichthyosauri and Plesiosauri are found, some of which 

 must have been from animals of enormous size. My notes say that 

 "a single vertebra of Plesiosaurus taken from the tunnel weighed 

 ten pounds." This is from information obtained from the workmen 

 during the progress of the works, when the line was being con- 

 structed. 



Near the village of Flitwick are two cuttings in the Lower 

 Greensand, besides several sand-pits in the immediate vicinity. 

 In most of the sections, especially the one near the railway-station, 

 the dip of the beds is well exhibited. They consist of yellow and 

 nearly white sands, alternating with dark bands of ironstone. This 

 series of beds extends across the county beyond Sandy in a north- 

 easterly direction, and near Leighton Buzzard towards the south- 

 west. At Silsoe, about four miles east from Flitwick, is an extensive 

 pit, in which is exposed a hard compact dark brown sandstone. 

 This furnishes a building material which has been used in the 

 locality for a long period, and is apparently that from which the 

 present Silsoe Church has been constructed. So extensive is the 

 sand-pit that much of it has been turned into a plantation, in the 

 shade of which, on the ancient facings of the stone, numerous 

 mosses and ferns luxuriate. 



The cutting south-east from Westoning passes through a bed of 

 dark heavy clay, which is apparently Gault. It exposes a continuous 

 band of coprolitic nodules, which averages about a foot in thickness. 

 This layer passes through about one-third of the northern portion of 

 the cutting, and is parallel with the general dip of the beds of the 

 locality. The fossils obtained when the section was first examined 

 were Lamna, Belemnites, Terebratula, and Parasmilia. 



Near the village of Chalton, in the parish of Toddington, the 

 hills forming the Lower Chalk escarpment are pierced by an 

 extensive cutting more than a mile in length. In addition to the 

 exposure of beds in this excavation, there are also some large lime-' 

 works near the north-east end, close by the railway, in which are 

 sections on a higher level than those of the adjoining line. Until 

 the present year (1889) these have been for several seasons in 

 active operation, and a considerable section of chalk is exposed. 

 Consequent upon the abandonment of the works, a considerable 

 talus has accumulated at the base of the deepest rock-face, which 

 obscures some portion of the section that was formerly visible. In 

 other parts of the workings the vegetable soil has been taken off by 

 the workmen, leaving exposed tabular masses of Totternhoe Stone, 

 which have been weathered into moderately thin plates, presenting 

 a most desirable condition for seeking the contained fossils. These 

 are both characteristic and interesting, and a diligent search will 

 soon be rewarded by at least several forms of Brachiopoda. At the 

 end of this paper is a list of the fossils both from this locality, and 

 the other principal sections. A few of the most noteworthy obtained 

 from the adjoining cutting, deserve, however, a passing notice. 



