Section IV, 1921 [105] Tr.\ns. R.S.C. 



On the J\fispec Group {Devonian) 



By G. F. Matthew, LL.D., F.R.S.C. 



(Read May Meeting, 1921) 



In arranging and naming the stratified rocks in and near St. 

 John, N.B., while their age was still to a great extent uncertain, and 

 fossils had been found in but a few places, they were divided into 

 several groups partly on the basis of the degree of metamorphism 

 which they exhibited and partly from other causes, as, for instance, 

 their apparent succession; they were found to lie in the following 

 order : 



The Portland Group 



The Coldbrook Group 



The St. John Group 



The Little River Group 



The Mispec Group 



The highest of these (viz., the "Mispec") is that which forms the 

 subject of the following communication, but they all were character- 

 ized by slaty cleavage in the finer beds. The writer emphasizes the 

 slaty condition of the "Mispec" because in this it differs from the 

 overlying formations and resembles those below. But as the "Mis- 

 pec" was sometimes found to rest on other rocks than those of the 

 Little River Group, it has evidently been formed independently of 

 that group and not with it as at first was supposed. 



Most palaeobotanists will agree with Sir William Dawson and 

 Mr. David White that the plant beds of Perry in Maine are Upper 

 Devonian; therefore a knowledge of the facts bearing on the age of 

 the "Mispec" Group, which is the stratified formation that immedi- 

 ately underlies the Perry beds in their eastern extensions would be of 

 some importance in connection with the latter. So I propose to tell 

 what has been learned of the geological age of the "Mispec" 

 beds, since Sir William made his study of the strata around St. John. 



The relations of other formations which have a bearing on the 

 age of this group may also be mentioned here. About thirty miles 

 to the northward of St. John are limestones whose Lower Carboni- 

 ferous brachiopods have long been known; these give us one horizon 

 of a fixed geological \aluc. Just beyond and to the northward of 

 these (and above them) is the southern edge of the great Carboniferous 



