38 'IIIK UK A»iK IN CANADA. 



IVdsi. The lidiildcr-cliiy iisiiiilly i-csts directly on sdiuicd 

 rock-siiil'i(('('s : hilt I liiivf (tliscrvcd in Ciiiu' r>icti)ii n 



peaty III' liinwii cuiil dc|)( 1 ilh Idillielies of eniiit'erniis 

 trees, wliieli liiidei'lies il, il in dtliei" pliiee-* there ill'e 

 deposits of rolled ^M'tiNel under thi' lioidder-elay. At/ the 

 (ili'n hrick-work, n«'ar Monlii-id, a pcenliar modified 

 houlder-elay occurs, consist in^f of \ery irreu'iilaily hedded 

 Hiuid and i^rascl, uilli many lar^v liouldeis, and only thin 

 lavers of elav. 



The stones of the iMudiler-elay are often scratched, anil 

 •jround into those pecidiai' wedi^t'-shapes so chai'aclei'istic 

 of ice-worketl stones. \'ery ahundant exami)li's of tins 

 occur at Montreal ami in its \icinity. 



Al Isle N'eite, l{i\ icre (hi i-oiip, Muriay I>ay, (,)iieliec, 

 St. Nicholas, Little Metis, etc., the hoiilder-clay is fos- 

 siliferoiis, containing' esj»ecially Lnhi iihnidliK, and often 

 haAin^' hoiilders and lar<,'e stones »'overe(| with lidhnnn^ 

 Jf((iiuri i\\u\ with r»ry(»/oa, i'\idenciii,L!,' that they ha\'e. for 

 some time ([iiietiy re])osed in thi^ sea bottom hefoie heiny' 

 huried in tlu^ clay. This is imleeil the; usual condition of 

 the houlder-elay in the lower part of the St. Lawrence 

 river.* Further ii]t, in the vicinity of Montreal, it has 

 not heeii oltserved to contain fossils, hut it ])resents 

 eipially une(|uivocal evidence of suh-a(pU'oiis oriirin in the 

 low state of oxidation of the iron in the hliie clay, which 

 becomes hiown when e.x^io.sed to the wciithei', and in the 

 bri<,'htiiess of the iron ])yrite.s contained in some of the 

 glaciated stones, as well as in the presence of rounded and 



* Uphain lulniits ( Proc. Brit. Nit. Soy., 1888) that sea shells exist 

 in the boulder-olay of MassaeiiuseHs ; hut his exi)laiiation tluvt tliey 

 have been pushed up hy glaciers is (juite iuadiiiissilde, more especially 

 as they are not of more boreal types than those of Massachusetts bay 

 «t present. 



