13 



menites, in another finu-graineil, or impure sands, in ;x tliinl cliiyish i^rts t(i 

 Ih3 gathered and deposited together. Thus, we see along the coast surround- 

 ing the plain of Tokio, sands and clayish soils alternating and ofton occurring 

 close to one anotiier, according to the degree of exposure or jiiMtection of th« 

 part of the strand to which they belong. Thus, sandy deposits prevail along 

 the open coast, especially along the eastern coast, but there are also pirts of the 

 shore of the Tokio-Bay which are sandy in consequence of their being exjiose«! 

 to the direct influence of the waves of the sea. One of these iilaces is to be 

 seen along the road from Yokohama to Odawara, and is one of the best examples 

 of this kind. Another kind of soil, which is not very freipiently met with near 

 Tokio, is also found near Yokohama — the ]ieat and peaty soil. Near Takigashira- 

 mura we have the following section in those parts which cover the strata to he 

 mentioned in one of the following chapters, and wliicii at the s;\me time are 

 situated nearer to the sea : 



1 Meter of sandy clay, blackish and intermixed with pent. 

 0.6 — peaty substance. 



0.5 — impure sand, colomed dark by peaty admixtures. 

 0.2 — 0.3 loose conglomerate (rounded pebbles with dark and .some- 

 what peat-L'olonri'd soil letween). 

 0.4 — impure sand mixed with pebbles. 

 Under this layer we have that line of umcomformability, which .separates the 

 quaternary beds from the tertiary deposits, and which we shall di.scuss hereafter. 

 The la\'er next to tliat line is a shell-layer of a similar importanei^ and of the 

 same character, mostly also containing the very .same species, as th.-it of Oji. 

 As to it, we refer to the Cth chapter, and add here only, that clayish soil, always 

 a little sanily, is widely dispersed through the b.iy near Takigashira, in whirli 

 we find a profusion of snrh species of shells which seem to be typical fur calm 

 and shallow water, e. g. the Lam]>iviii;e {L. midtitormis Lischke and zcinalis 

 r.amck). It is therefore not astnni.-hing to (hid near this jiart of the coast, on 

 the low grounds which are cut by the canal joining the liay wilh tlie liarl)uur of 

 Yokohama, those alluvial deposits which indicate the calmest and most stagnant 

 waters. Of cotirse the.'se j>eat-deposits are truly alluvial, a.s is clearly shown by tliu 

 underlying pebbles, to some of which recent oysters are attached, wliich however 

 ill their ori'.^iii have been certainly di!n\ial. M(»st of tlic-e peliblcs at lejist form 

 a diluvial layt.'r wldch only in ils u]tper parts seems to have lieen greatly alfected 

 by alluvial waters. The lower parts of llie river-lu'ds are likewise nunc 

 clayish — aiidiri scimo instances |K-aty — within the bay than on the easlern eoist, 

 wiiere sands prevail olten to soiiii' di.slainc iVoiu ihr sea. 'I'liis (-.1111101 !»• wfll 

 expl.iined b_v any dili'erence In'twceii llif liver-courscs themselvi's, but it is 

 jterfectly accounted tor on the .supposition that llic siuue causes acted upon the 

 land befoR' it nwheil its present extension, at a time wlien the slioro was situated 

 nearer to the Ijase of the biulVs, but when the elevated bhilfs were already in 

 existence and ofiposcd to the low level-plain. This period, of course. iH-lonir» to 



