R. H. Rastall — Rocks of New Zealand. 403 



ice-sheet to have been coming from somewhere between west and 

 south rather than north or east — a mighty volume of frozen water, 

 not from. Scandinavia or Scotland, but from the mountainous region 

 which environs the Wash ! 



We conclude by recapitulating, in addition to these more general 

 objections, the heads of the evidence, which, as shown above, we 

 have collected during our visits, and find irreconcilable with 

 Mr. Eeid's hypothesis : — 



(1) The bending of the chalk, as shown by the flint bands, is 

 very variable (notably at Trimingham headland), and not seldom 

 practically disappears, affording no evidence of regularity of 

 distribution. 



(2) The chalk in immediate association with the glacial drift 

 does not occur, even at Trimingham, as a continuous mass, but in 

 separate fragments. 



(3) The bedding of the drift, where in contact with the chalk, is 

 generally almost, if not quite, horizontal ; at any rate, it shows that 

 this lower part cannot have been crushed up with the chalk. 



(4) But above these horizontal beds others may occur which are 

 contorted, and sometimes to an extraordinary extent. Thus their 

 flexures must be due to some other cause than that which Mr. Keid 

 invokes to produce the bending and uprooting of the chalk and 

 immediately adjacent drift ; for if a second advance of the ice-shfeet 

 be postulated in explanation of these, it was content, on the second 

 occasion, to leave the drift below it undisturbed. 



(5) Lastly, chalk-masses occur east and west of Trimingham 

 'headland, insulated, like great erratics, in the drift without any 

 appearance of crumpling up, so those at that place do not demand 

 a special explanation. 



Thus Time, as we venture to maintain, has delivered its verdict 

 against an hypothetical interpretation of these Trimingham masses, 

 which in our opinion ought not to have found a place in a Survey 

 memoir. They are simply huge boulders, like the other chalk 

 •masses east and west of Cromer. We have, of course, adopted for 

 our own use an explanation of these and of the extraordinary 

 contortions of the drift ; but as we do not yet exalt it from hypothesis 

 to theory, and as the purpose of this paper is destructive rather than 

 constructive, we think that any definite statement of it would be 

 unnecessary. 



III. — Notes on some Eocks from New Zealand. 

 By R. H. Rastall, B.A., F.G.S., Christ's College, Cambridge. 



THE specimens on which the following notes are based were 

 collected by Mr. H. T. Ferrar, M.A., F.G.S., while on a torn- 

 through New Zealand, during the time the " Discovery " was being 

 overhauled in Lyttelton, on her return from the Antarctic. The 

 topographical and field notes were also supplied by Mr. Ferrar, and 

 it must be clearly understood that only the detailed petrographical 

 •descriptions are the work of the present writer. 



