TRANSACTIONS OF THE SECTIONS. 



97 



On Insect Bemains and Shells from the Low^.r Bagshot Leaf-hed of Studland 

 Baij, Dorsetshire. By G. M.\w, F.G.S., F.L.S.] F.S.A. 



The author exhibited a large series of insect-remains, collected by Mr. W. E.. 

 Brodie, from the Lower Bagshot Leaf-bed of Studland Bay, the species of which 

 had not yet been determined. Also six or seven shells belonging to the Unio- 

 nid;B ; these were of special interest, as heing the first mollusca that liad been 

 found in the beds separating the Middle Bagshots and London Clay, and deter- 

 mined the freshwater origin of the Lower Bagshot clays, a view Mr. Maw had 

 previously advocated from the physical characters of the beds. 



ExjJeriments on Contortion of Mountain Limestone. By L. C. Miall. 



The author cited previous experiments illustrating the behaviour of various 

 materials when subjected to pressure, and briefly' described the geological pheno- 

 mena of contortion. An apparatus was exhibited, which had been prepared to 

 produce artificial contortions in laminre of rock, and to ascertain the amount of 

 defiection capable of being caused by sudden and continuous strains respecti^•ely. 



The lamina is clamped at one end to a block, the length to be bent is regulated 

 by sliding the block along a groove, and a known weight descends upon the free 

 end. Provision is made that the weight shall act upon a knife-edge, which is 

 always perpendicular to the surface of the slab, and ahvays applied to the same 

 line. By means of an index the deflection can be read accurately to hundredths 

 of an inch. 



In the annexed Table the results of one series of experiments are given. A 

 number of observed facts are neglected in order to give prominence to the chief 

 point, viz. the difference in the deflections produced hy the sudden application of a 

 considerable weight, and by the prolonged action of a force of low intensity. The 

 angles have been deduced from the amount of perpendicular deflection, and they 

 are consequently all taken as rectilinear. 



On a Specimen of Teleosaurus from the Upper Lias. By C. Moore, F. G.S. 



In connexion with this paper the author exhibited a specimen of Teleosaurus 

 temparulis, Blainville, about 4 feet in length, which was enclosed iu fine sections 

 of nodular yellow stone, as they originally came from the tfpper Lias quarry, and 

 which, when joined, looked like an elongated French loaf, iu the centre of which 

 the bones were covered up. It was stated that, when de-^-eloped, the Saurian was 

 likely to be found in very fine preservation. The beds in which it occurred and 

 the other associated organic remains were shortly noticed. 



1869. 7 



