340 Professor T. G. Bonney — Desert Conditions in the Trias. 



layers of sand, extends to the pit floor.' This is varied occasionally 

 by irregular seams of fine gravel (stones not bigger than a walniit) or 

 by lenticular streaks of sand, not exceeding a few inches in thickness. 

 Ovoid pebbles generally lie with their longest axis horizontal, but 

 in false-bedded parts this follows the dip. Plenty of sand is usually 

 present in the gravel. — [h) Pit nearer to the enclosure of Shugborough 

 Park. The beds exposed (probably just underlying those seen in the 

 other pit) afford a section about 1 8 feet at thickest. It will suffice to 

 say that we find in this a gravel, like that in the other pit, with long 

 thin lenticular beds of sand, horizontally intercalated. Here also the 

 longer axes of the stones are horizontal, sometimes conspicuously so ; 

 the whole mass, like that in the other sections, suggesting a fluviatile 

 origin. 



Several times, while making the above observations, I examined 

 the sand with a strong lens, and found my recollections to be correct," 

 viz., that, while rounded grains occasionally occur, the majority are more 

 or less angular : hence material, presumably water-borne, dominates 

 considerably over wind-borne. Thus, while I do not deny that the 

 conditions in the British lowlands during Triassic times resembled 

 those of a desert region more nearly than they do at present, 

 I think that the Liverpool district, to which Mr. Lomas's observa- 

 tions refer, must be a rather exceptional one. Unfortunately, my 

 acquaintance with this is slight, but my studies of Triassic deposits, 

 both in Central Staffordshire and in other parts of England, have led 

 me to believe that, even in Keuper times, water played a larger part 

 than wind in their formation. 



P.S. — This paper was written early in the year, but as I was 

 leaving England for some weeks in the spring it was kept back, 

 because I wished to add a few words on some pebbles which I had 

 not previously noticed in the Bunter. They occurred in the Style 

 Cop pit and in that near the Waterworks. In each case they were 

 restricted in vertical range, not at all common, the longest diameter 

 generally under two inches, flattish, but fairly well rounded, less 

 than the ordinary weight, damp, soft, and dark-coloured (becoming 

 paler when dry), with an amber-brown streak. At the time I thought 

 they might be a rotten cannel, or at any rate rather rich in some 

 hydrocarbon. On examining under the microscope, after my return 

 to Cambridge, the powder from one of them, I found no traces of 

 organic structure, though some translucent brown particles suggested 

 the presence of a bituminous constituent among the ordinary mud- 

 like material. But Professor Sewai'd, who kindly made a more 

 complete investigation, informed me that he could not detect any traces 

 of plant tissue, and Mr. A. Hutchinson, University Demonstrator in 

 Mineralogy, to whom I am indebted for examining a fragment during 

 my absence, writes : " It does not contain carbon, but appears rather 

 to have resulted from the oxidation of some metallic ore. In the 

 main it consists of hydrated iron oxide together with a certain amount 



1 A few of the largest stoues even exceed 6 inches in diameter. 



2 See Quart. Journ. Geol. Soc, vol. Ivi (1900), p. 288; Proc. Liverpool Geol. 

 Soc, 1901-2, pp. 230-233. 



