480 Geological Society : — 



forced up on the western side, and has the aspect of having been at 

 least twice subjected to pressure ; as if one portion of the semifluid 

 mass had been displaced, and another subsequently pushed partly 

 over it, by successive footste])s. The author supposes these impres- 

 sions to have been made by the same kind of animal as that which 

 gave rise to the foot-marks on the Permian sandstones of Corncockle 

 ftluir, and which has been termed Chelkhius by Sir W. Jardine. 

 TlieTintwhistle tracks are referable to a much larger animal than even 

 the C. titan of Jardine, and Mr. Binney proposes to call it C. ingens. 



2. " On the Lignite deposits of Bovey-Tracey, Devonshire." By 

 Dr. J. G. Croker. Communicated by the President. 



The author first described the physical features of the basin, sur- 

 rounding the junction of the Teign and Bovey Rivers, in which these 

 beds of lignite and their associated clays (used in pottery) are found. 

 The lignite-beds come to the surface at Bovey Heath towards the 

 north-western margin of the basin ; they underlie towards the south- 

 east about 11 inches in the fathom, and are covered by clays and 

 gravels ; their vertical thickness is about 100 feet. In the upper 

 portion of the lignitic series are several (five and more) beds of 

 loose lignite, covered and mixed with variously-coloured clays and 

 granitic detritus ; a ferruginous sandy clay, 9 feet thick, succeeds, 

 which is followed downwards by ten beds of " good coal" or lignite, 

 separated by bluish clay-beds and worked for fuel. 



Fir-cones, referable to the Scotch-fir {Pinvs sylvestris), have been 

 found in one of the uppermost layers of loose lignite. Large flabel- 

 liform leaves also are represented by fragments 2 feet long and 

 20 inches wide in some of the higher beds, together with tangled 

 masses of vegetable remains. In the second and fourth beds of good 

 coal (the latter about 80 feet from the surface) the lignite abounds 

 with the little seeds lately described as Folliculites minutulus by 

 Dr. Hooker in the Society's Quarterly Journal. The lignite gene- 

 rally is composed of compressed coniferous wood, and retin-asphalte 

 is locally abundant. The Bovey basin is about 60 feet above the 

 sea-level, and was almost a swamp until it was drained within the 

 last ninety years. A peat-deposit, in which fir-timber is found, 

 covers the lignites towards the south. 



The author also referred to the extensive denudation that the 

 district has undergone, and pointed to the Dartmoor granitic tract as 

 the source of the clays of the lignitic deposits. He also noticed the 

 several M-riters who have treated of the lignites and the geology of 

 the neighbourhood. Lastly, Dr. Croker su])plied some notes on the 

 local occurrence of the numerous varieties of rocks and minerals in 

 the vicinity of the Teign, such as ores of lead, manganese, and iron, 

 also labradorite, schorl, &c., all of which, as well as the lignite and 

 its vegetable remains, were illustrated by a large series of specimens. 



3. " Notice of some appearances observed on draining a Mere 

 near Wretham Hall, Norfolk." By C. J. F. Bunbury, Esq., F.G.S. 



About Wretham, six miles north of Thetford, are several meres, 

 or small natural sheets of water, without any outlet. One of these, 

 about 48 acres in extent, has been lately drained by machineiy, for 



