﻿52 W. S. Shaler — Geology of Cobscook Bay District, He. 



as data for the identification of their age. Of the hundred or 

 so species of fossils which have already been approximately de- 

 termined, the greater part are either distinctly unlike those 

 obtained elsewhere, or belong to forms which have a wide 

 vertical range in the rocks of other districts. A number of the 

 most interesting forms are so far novel that they offer no evi- 

 dence of value as to the age of the beds in which they occur. 

 Moreover, judging from the other known deposits of middle 

 Paleozoic age on the Atlantic slope, those of Newfoundland. 

 New Brunswick, and Nova Scotia, the typical divisions of the 

 New York section or of the Mississippi valley, do not re- 

 tain their limits on the eastern shore of the continent. The 

 Silurian deposit of Antieosti cannot be precisely paralleled 

 with those of the interior basin and much the same lack of 

 definite relation to the western section is found in all the 

 horizons which are represented on the Atlantic coast basins. 

 This difficulty is one which might fairly be expected. The 

 faunal divisions in contemporaneous strata of the Paleozoic 

 rock though less clearly marked were hardly less numerous 

 than those of the present day, i. e., the faunal areas whether 

 determined by the difference between deep sea and shallow 

 water, or by the difference between the sides of a barrier such 

 as separated the Paleozoic deposits of the continental basin 

 from the Atlantic coast were as numerous as those in the ex- 

 isting seas. 



Although these divisions were nearly as distinct in the Pale- 

 ozoic era as found at the present time, there was, it is true, no 

 such delimitation of zoological or botanical provinces as at 

 present; no such difference as those which now separate the 

 Australian from the American province existed in the Paleozoic 

 time, but the lesser differences of faunal divisions, though not 

 so much accented, were something like as numerous as at 

 present. It is therefore by no means surprising that we find 

 difficulty in determining the relations between the deposits of 

 the Cobscook series and those of the typical western series of 

 the continent. 



The Cobscook series presents us with the several sets of beds 

 which in their physical characters and their organic contents 

 seem to indicate separate horizons. By far the richest horizon 

 yet found in this series is that which is shown on the west side 

 of Orange or Whiting Bay about half a mile south of Ball's 

 Mill. At this point the fossiliferous strata are seen with a 

 thickness of about twenty feet. On the west they are cut off 

 by an extensive series of dykes and in the east they dip below 

 the level of the bay. 



These beds are only exposed below high tide mark which 

 fact made collecting in the few hours on two days when the 



