438 NOTE ON THE SVDNEY COAL FIELD — OILPIN. 



wlio I'emarked, "that it was composed principally of leaves 

 pressed in grey shales and remarkable for furnishing several 

 species of ferns with the fructification. The horizon is stated 

 to be that of the millstone grit, but the determination of the 

 plants would not convey that impression, being of species not 

 occurring elsewhere except in the coal formation, and even in 

 the upper part " He further remarked that a similar group of 

 plants appears in a collection made at Henderson's pit on Black 

 Brook, about four miles to the south-east near the point already 

 alluded to as the turn of these measures at the end of the 

 synclinal The occurrence of a well marked group of fossils 

 characteristic of the productive measures in this isolated position, 

 surrounded by miles of strata of millstone grit age, and 

 separated from the nearest known productive coal measures by 

 a distance of several miles, appears at first sight unaccountable. 

 When, however, the effect of the fault already described is con- 

 sidered, it appears probable that in this area the millstone grit 

 supports a narrow trough of higher strata. At present it is 

 impossible to correllate the beds already exposed with any of" 

 those known in the (jUace Bay district. 



Considering the subject from the point of view expressed by 

 8ii" William Dawson, that the fossils are characteristic of the 

 upper portion of the productive coal measures, it is difficult to 

 believe that the lower portion of the horizon can be presented in,. 

 the Cossitt Basins with the equivalents of the seams now being- 

 worked at Glace Bay ; and the hypothesis may be hazarded 

 that at this point the deposition of the later memV)ers of the- 

 strata, comprising the productive measures, took place over rocks 

 of millstone grit age without the intervention of the middle and 

 lower portions of the productive measures 



Putting aside the fossil evidence it may be remarked that the- 

 sections exposed so far in the Cossitt Basin recall the series of" 

 small seams associated with the Martin seam near Bridgeport. 

 It may, however, on fui'ther exploration be found that the 

 Murray seams passing to the east of the Sydne}" fault out- crop 

 along the range of the Fitzpatrick seam and coincitle with the 

 Co.ssitt seams as they are brought up on the opposite oi'. west, 

 side of the fault. 



