Vol. 50.] THE OSSIFEROUS FISSURES NEAR IUHTHAM. 171 



14. The Ossiferous Fissures in the Valley of the Shode, near 

 Ighthasi, Kent. By W. J. Lewis Abbott, Esq., F.G.S. (Read 

 January 24th, 1894.) 



Contents. t, 



Page 



I. Introduction 171 



II. Fissures in the South-east of England : History of 



the Shode Valley 172 



III. Description of the Fissures near Ightham 177 



IV. The Fossil Plants and Invertebrata found in the 



Fissure 181 



V. Conclusions 185 



I. Introduction. 



Doubtless there are many geologists in common with myself who 

 have recognized the fact that, if the surface of the Wealden area has 

 been subject to the oscillations claimed for it, then, considering the 

 unyielding nature of the lime- and sandstones, we ought to find in- 

 numerable fissures, and by the law of chances these ought sometimes 

 to occur in positions favourable to the preservation of those hetero- 

 geneous collections of objects that find their way into the drainers of 

 a country. There are few, perhaps, who realize what a motley group 

 of curiosities are to be found in large streams, unless they have spent 

 some considerable time in walking between the tide-marks of a river 

 in its lower reaches. It is not often conceived how large a portion of 

 the life of to-day could be rescued from such a wreck. Here may be 

 found bones of animals by the cartload, and the hard parts and fruit 

 of vegetation, both terrestrial and aquatic. The principal non-marine 

 mollusca are also represented, although the majority of shells are 

 usually of aquatic species. To appreciate the profusion of these 

 relics one need only travel for the same period over land-surfaces and 

 note the difference of the result. I have frequently paced scores of 

 miles over fields, foot by foot, chiefly in search of implements, with- 

 out finding a single bone of an animal of either terrestrial or aquatic 

 habits. 



It is extremely important to bear these two conditions in mind 

 when we try to account for the filling of fissures and caves with 

 the materials that we now find in them. I have thought it 

 absolutely necessary to draw attention to these important facts, 

 because I regret that I am obliged to differ in opinion from so 

 great an authority as Prof. Prestwich as to the manner in which 

 caves and fissures have been filled. The successive faunas of the 

 various strata, their stalagmitic sealing-down, the identity of the 

 contents of fissures with river-debris, and their total dissimilarity 

 to ordinary land- wash, together with other collateral characteristic 

 features, to my mind render these deposits incapable of being the 

 result of a marine immersion. 



Unfortunately, the literature of the "Weald would not encourage 



n2 



