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HKMAINS IN Tlir, C'().\1,.|'()U.MATI0N OK NOVA SC'OTFA. C25 



After !i ([uii't iiciiiimiliitiiiii uf ve;;t'tiil)lo iiiiittor, siiHiricnt to give six inclios of pure 

 c<ml,tli(' iuvii must Iiiivo ,siili.si(l(>(l or lict-ii ovcillowcd witli wuttT, ]in)lt!iljly luackisli, in 

 wliirli Xuiiiililfii and KiitoiiiostijicaiiH cstahlislied theinsolvf.s, l)iit in wliicli lor a time 

 very little sediment was deposited, the dead plants remaininjjf on flie surface of the 

 suhmerged swamp, and possilily otiu rs (Iriftuil to the locality, formini,', with a little iiiie 

 argillaceous matter, the material ol'carhDiiaceous shales. Jii the meantime the stronj,'er 

 and lar,i;er tnuiks of the Sl;/ill(iri(i forest remained erect, and arouiid their bases there 

 j,'radually accumulated layers of mud, constituting' the shale. No. 10, iucludiiij,' drifted 

 jilants, while it is not unlikely that the ahundant remains of SphciKijiln/lluin and 

 PiiiiiiilnrKr re|ircscnt aiju.itic vcifctatlon ^'rowing on the surfaces of the accunndating 

 nuid. At this tinie the greater iium!)cr of the trees had either not yet become hollow 

 (tr were too tall to receive any scdiineMt. A few, to be noticed in the se(piel, were 

 littwever either wholly or in part lillcd with clay. 



]5y gradual silting >ip, |iMs>i]ily iiidcd by u slight elevation, the area again became 

 capable of supporting land plants, as evidenced liy the elect Ca/ainile.-< and Calnmo- 

 iJiiidni which rise i'mia the surliice uf iIk' shale, and by tlu' Sflijimirid' in the succeed- 

 ing sandy deposit. The siul'ace ImweVfr imw became subject to periodical or occasional 

 inundations bearing sand, at lirst tine and ;iigillaceous, but al'terwards coarser. In the 

 intervals of these inumlations the thickets of Calitmife.s and leriis which occupied the 

 ground wert! tenanted by JJatrachians, Millipedes, and f uid SnailN. 



In the meantime the larger and stronger Sl(/lll< , whic-h had remained erect, 

 while sand was aeennnilating iimund theii' trunks, lu'came hollow through decay, the 

 strf)ng outer lind alone icmaining. w liilc the inner bark iuid woody axis lell to pieces 

 and dropped into the bases of tlii' hollo.v c\linders. In this condition these hollow 

 ti'ces would constitute deep wells and pits in the soil, their openings more or less 

 masked with herbage or with slavds of Iwnk projecting id)ove the surliice. They no 

 doubt served as ]>laccs of retreat to Millipedes and Land-Snails; but to the Kmuli 

 reptiles luH'dles>,ly passing over the stwface ihey were pitiidls into which they fell, and 

 bi'ing luiable to escape, perislnd. 



In coimexion with this, it shoulil be ohserved that the conditions of the case 

 excluded all animals unaltle to civep or walk on land. Hence the assemblage of 

 s[»ccies in these tiunks is of a special diameter, and includes none of those more 

 a([Uatio forms nf I'atraehlans which have lieen discovered in the a(|Ueous dejtosits 

 of the i)eriod. Further, tmly the smaller animals of the locality would be entrapped, 

 larger specaes being little likely to falj Into ..jienings so i.arrow. 



How long anv of the hollow trees rcniaini'il open it is impossil)le to say; but there 

 is, as mi^lit I'c expected, I'vidence of successive stages and dilfcrent modes in their 

 tilling. Some shoit bases of tiees, restlnL;' on the coal and not extending udo the 

 shale. !i.;e mere disks ol' mineral chaivoal, and may represent trees which had gone to 

 decay e\en before the lirst sulinuigencc of the coal. Others seem to have been 

 broken olf betbi-e the close of the deposition of the shale, and aie tilled with that 



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