118 A. R. Horivood — Upper Trias of Leicester si tire. 



ill form, .spheroidal, pure, and ver}- liard; (3) fibrous gypsum or 

 satin spar, having the crystals vertically arranged; (4) selenite, 

 liaving a typical crystalline form, often twinned, or in laminae, or 

 plates. Tlie selenite is often encrusted upon the outside of the ball 

 gypsum, and is stained a chocolate colour. The gypsum is white or 

 yellowisli -white, pink, or greenish, especially when traversed by 

 Green Marl. The latter may under- or overlie a seam of gypsum. 

 Fibrous gypsum passes laterally' into ball gypsum, and often 

 anastomoses. Pseudomorphs of salt crj'stals are abundant upon the 

 surfaces of the green bands, varying in size from \ to finch across. 

 They are associated with ripple-marks. 



There is an interesting case of what maybe regarded as undulatory 

 bands of coloration, where a thick green band below the thick 

 gypsum band exhibits a dip or syncline, transgi'essing a cliocolate 

 band below. The bedding is horizontal throughout, and this shows 

 that coloration here, at least, is secondary to bedding. On the 

 view that the green coloration is original and tlie red due to 

 percolation by influx of chalybeate water, as held by Dr. Moody, 

 the red coloration of the lower band must have been applied from 

 below upwards, and the dip in the green colour would be due to the 

 different porosity of the latter, or its composition influenced by its 

 greater specific gravity. 



The ripple-marks trend north 20° west. They are practically 

 upon the top of the thick green band near the top of the section. 

 This is not seen elsewhere,' for at Glen Parva the floor is upon 

 a layer of pink granular gypsum. In some parts the top is covered 

 with small slabs (1 X 1 X 2 inches) of this granular salmon-pink 

 variety. At others there is a peculiar hard pink kind of skerry 

 passing into greener marl with a pink layer of gypsum below. The 

 hard pink layer is semi-crystalline, and resembles the band at 

 Vass's Brickyard, into a form of which it passes, containing here 

 and there hollow cavities, and in large measure also dolomite. 

 The steeper side of the ripples faces north-west, so that the 

 direction of any current would be at right angles, i.e. from the 

 south-west. 



At Vass's brickyard, a little to the north, a section 14 ft. 4 in. to 

 26 ft. 6 in. exhibits lied Marl with tliree Green Marl and skerry 

 bands, and a floor of gypsum. The marl here is not so hard as at 

 Gipsy Lane, being more sandy. I found some pseudomorphs of salt 

 crystals on what were apparently Red Marl slabs, but subsequent 

 examination showed that it had been stained red. Mr. Whitaker. 

 I believe, has found pseudomorphs on lied Marl. The junction of 

 the red and green bands is irregulai', with concretionary masses. 

 The dolomite with hollow cavities contains casts of what might be 

 taken for organic structures, but they are too indefinite to base any 

 decided opinion upon as yet. A curious skin is to be noticed upon 

 the exterior of some of the gypsum, which lies here nearer the 

 surface than at Gipsy Lane, and this must be due to recent chemical 

 change, just as another block of ball gypsum was pitted and fretted. 



In Barrow's pit, east of the Midland Railway, 33-46 feet of 

 ' Except near Gotham. 



