Alfred Bell — The Succession of the Crags. 209 



to frequent changes, wliich are much promoted by the cropping of 

 the grass by the cattle or by any artificial or accidental breaking of 

 the surface. At St. Peter's I saw an old entrance used in the early 

 French times quite filled up with the blown sand ; and I was told 

 that a hill 40 feet high had been removed within a few years, aiid 

 had disclosed the remains of an old blacksmith's forge under its base. 

 The sand in these hills is derived from the waste of the red sand- 

 stones ; and, when left dry by the tide, is blown up by the wind. 

 The attrition to which it has been subjected has removed the coating 

 of red oxide of iron from the siliceous grains of sand, so that, though 

 derived from red rocks, these sands are nearly white. Where the 

 sand-hills run along the coast, a long narrow channel often occurs 

 between them and the shore, and they often block up streams, 

 forming lagoons, in which deposits very different from those of the 

 open gulf are produced. 



Mr. Pope kindly pointed out to us on a creek near Grand Kiver, 

 and on Ives Creek, the mounds known locally as " shooting-dykes," 

 in allusion to their use by sportsmen as a shelter in duck-shooting. 

 These are somewhat regular banks or dykes of soil fringing the 

 creeks, and having almost the appearance of artificial earth-works, 

 which they have indeed been supposed to be. Some of them are six 

 feet in height and ten feet wide at base. I believe them to be of the 

 same nature with the Lake Ridges of Nova Scotia described in my 

 Acadian Geology,' and that they have been produced by the expansion 

 or driftage of the ice, which forms in the creeks in winter. They 

 constitute a sort of " Moraine " deposit, which, on a larger scale and 

 in a more hilly country, might readily be mistaken for the work of 

 glaciers. Those that we saw were entirely composed of soil inter- 

 mixed with vegetable matter. Some of them showed evidence of 

 formation by successive increments of material. Their steepest sides 

 were next the land, and they were highest opposite the most exposed 

 and widest portions of the creeks. 



rV. — The Succession of the Cbags. 

 By Alfred Bell. 

 A LL geologists, especially those who, like myself, are interested 

 XA in the study of the Upper Tertiaries, are indebted to Mr. 

 Prestwichfor the valuable memoir upon "The Structure of the Crag- 

 beds of Sufi"olk and Norfolk." * As the views propounded therein 

 are somewhat novel, I purpose examiniag some of the points brought 

 forward in their support. 



The presence of Diestien fossils in the Suffolk Crag, and the 

 cause of their being there, appears to me to be susceptible of a 

 simpler explanation than has been given. Mr. Lankester considers 

 them to be the remains of an older formation, which was broken up 

 by the Crag Sea. This will not account for all the phenomena 

 noticed, and I shall venture upon a few words concerning the older 

 Pliocene deposits. Between the Falunian (Upj)er Miocene) and 



1 Page 35. 2 Quarterly Journal Geol. Soc. London, 1870-ancl 1871. 



VOL. IX. — NO. XCV. 14 



