Geological Society of London. 275 



almost pulverized, and redeposited among the drifted materials. The 

 boulders vary in size from that of a man's fist to two or three times 

 that of a man's head, and are nearly all composed of rounded and 

 subangular masses of Lias limestone ; many of them are distinctly 

 striated with the ice-markings so familiar to geologists. Large and 

 small quartzose pebbles are extremely common, derived, in all prob- 

 ability, from the denudation of the Bunter, further north by a very 

 few miles. There is also much rotten Marlstone from the Middle Lias, 

 and a great quantity of re-deposited red Keuper marl. A few large 

 boulders of Carboniferous limestone are contained in the medley 

 mass ; and a fragment of Coal-measure Sandstone has also been 

 found containing the most distinct impression of a specimen of 

 Stigmaria, with rootlets attached : this is now in the possession of 

 Mr. Parry, the engineer of the line. For some portion of the slope 

 of the hill the Boulder-clay forms the surface of the ground, and it 

 caps the whole of the hill which lies between Plumtre and Stanton- 

 on-the-Wolds, though it is here covered by several feet of drift-marl, 

 free from pebbles and boulders, and evidently derived from the 

 Keuper formation, whose outcrop occupies a large area of the ground 

 in the neighbourhood. At the shaft the Boulder-clay is 70 feet thick. 

 In some places the Paper Shales have been eroded quite through, so 

 that the Boulder-clay rests immediately upon the lower grey marls 

 of the Bhsetic, which are very regular, and have the same thickness 

 (10 to 15 feet) here which they have in other sections in this country. 



"I have thought it right to send the Society this brief communi- 

 cation, though several months must elapse before the railway will 

 be lowered to its proper level. When this is done, we shall get a 

 section, I hope, second only to that at Westbury-on-Severn." 



IL— April 28, 1875— John Evans, Esq., V.P.B.S., President, in 

 the Chair. — The following communications were read : — 



1. " On Stagonolepis Bobertsoni, and on the Evolution of the 

 Crocodilia." By Prof. T. H. Huxley, Sec. E.S., E.G.S. 



After referring to his paper read before the Society in 1858, the 

 author stated that he had since obtained, through the Rev. Dr. 

 Gordon of Birnie, and Mr. Grant of Lossiemouth, further materials, 

 which served at once to confirm the opinion then expressed by him, 

 and to complete our knowledge of Stagonolepis. The remains 

 hitherto procured consist of the dermal scutes, vertebras of the 

 cervical, thoracic, lumbar, sacral and caudal regions, ribs, part 

 of the skull and the teeth, the scapula, coracoid aud intercavicle, 

 the humerus, and probably the radius, the ilium, ischium and pubis, 

 the femur, and probably the tibia, and two metacarpal or metatarsal 

 bones. The remains procured confirm the determinations given by 

 the author in his former paper, except that the mandible with long 

 curved teeth therein supposititiously referred to Stagonolepis proves 

 not to belong to that animal. 



Erom the extant evidence it appears that in outward form Stago- 

 nolepis resembled one of the existing Caimans of intertropical 

 America, except that it possessed a long narrow skull, like that of a 

 Gavial. The dermal scutes formed a dorsal and ventral armour, 



