TRANSACTIONS OK SECTION C. 707 



meationed on the plateaux and on the ridges, having consolidated into a crust, 

 almost like a cement pavement, which resists the action of the rain. 



Another interesting point was observed with regard to these massive beds of 

 recent material. Instead of one stream re-establishing itself along the centre of 

 the deposit, the tendency is for a new stream to form on each side at or near the 

 junction of the new ash" with the old valley slopes ; and as these streams deepen 

 their beds two new valleys are formed where only one previously existed, and 

 the walls of each are composed on the one side of the new ash and on the other 

 of older tuff, with occasional terraces.' 



An account was also given of a visit to Montague Pel6e, in Martinique, with 

 a discussion of the phenomena of the extrusion of and LabSequent destruction of 

 the spine which have been described by Lacroix and others, and a comparison of 

 the eruptions of the two islands. 



5. Recent Earth Movements withirt the Basin of the Laurentian Lakes. 

 By Professor W. H. Hobbs. 



With the substitution of the method of precise levelling for the aneroid and 

 the hand-level in the study of the abandoned shore-lines of the great lakes, a new 

 epoch has been inaugurated. It now becomes possible to correlate the observa- 

 tions with some measure of assurance, and thus to extend the chapters of the 

 Post- Wisconsin history of the lake region. Generally accepted views concerning 

 the recent tilling of the province are shown to require considerable modification, 

 and prophecies relating to the time of future changes of drainage fall away. 



6. Report of the Geological Photographs Committee. — See Reports, p. 245. 



7. Report on the Erratic Blocks of the British Isles.— Qee Reports, p. 242. 



8. Jfote on Casts of Dinosaurian Footprints in the Loiver Oolite at WJiitby. 

 By Haeold Brodeick, M.A. 



The two footprint casts found at Saltwick, a small bay to the south of 

 Whitby, were on blocks of oolitic sandstone which had fallen from the cliff above, 

 so that it is not possible to determine their exact horizon ; they must, however, 

 have been within 150 feet of the bottom of the oolites of that district. Both casts 

 are those of the footprints of a three-toed creature, and are similar to those of the 

 iguanodon of the Wealden beds, although on a smaller scale. The first of the 

 Saltwick casts indicates a foot with three functional toes, arranged m the form of 

 ft broad arrow ; the greatest length is 18 cm., the palm being 6-5 cm. in length, 

 thus giving a length to the middle digit of 11-5 cm. The side digits were about 

 9-5 cm. in length. The cast is formed of a very fine-grained sandstone, and for- 

 tunately the whole of the cast is shown, although it has suffered somewhat from 

 weathering. The second cast seems to represent the footprint of a slightly smaller 



while there is a deep corrugation across it as if the creature bad a loose fold of 

 skin under its foot. The total length is 12-5 cm., but it is probable that the 

 digits were really a little longer than now shown. On the same slab, and slightly 



' See, further, Anderson, Keport, Pait II.. Phil. Trans., Series A, vol. 208, 

 pp. 275-300, Flett, Petrology, ihid., pp. 304-333. 



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