[BAILEY-MATTHEW] NEW BRUNSWICK GEOLOGY 113 



cross section, five or six inches in diameter and exhibiting concentric 

 layers, which by weathering are made to project and to give to the 

 whole the appearance of a rosette. If really organic it would seem 

 to be of rhizopodan or foraminiferan origin, but there are those who 

 prefer to regard that origin to be mechanical and concretionary. 

 If we admit their organic derivation still another supposition is 

 possible, viz. that the limestones are due to the growth and accumula- 

 tion of certain types of seaweeds, as is now believed to have been the 

 case with the limestones of the Granville series. Even Bacteria may 

 have played an important part. The occurrence of serpentine with the 

 limestone at St. John, as at Grenville, is significant, as the magnesian 

 silicate may be only the altered form of the glauconite or greensand 

 which is so extensively associated with the foraminifera of Cretaceous 

 and later seas. 



The fossil alga (Newlandia) described and pictured by Walcott as 

 found in Algonkian rocks of Montana, bears in outward appearance, 

 great resemblance to the Archœozoon of St. John. See "Origin and 

 Evolution of Life," p. 102. 



Cambrian 



Some problems connected with the Cambrian of Southern New 

 Brunswick are the following: — 



(1) The relations of the Cambrian beds of the St. John basin 

 to the underlying Pre-Cambrian, and the evidences or otherwise of a 

 diastrophic break between the two. 



(2) The relations of the Cambrian to other systems as found in 

 the Kennebecasis and Belleisle valleys. The former distribution of 

 the Cambrian rocks, with evidences of extensive erosion. 



(3) The sources of the material constituting the several divisions 

 of the Cambrian series, with the probable geography of the era, its 

 currents and climate. 



(4) Sources and probable migrations of the fauna. 



Some of the above questions have been discussed at length in 

 various articles by one of the writers, and need not be further con- 

 sidered here. A few additional observations on other points may, 

 however, be made. 



Relations of the Cambrian to subjacent strata 



At the foundation of the Cambrian rocks near and at St. John, 

 we find an old "massif" or assemblage of strata certainly Pre-Cambrian 

 and probably of much greater age than the Cambrian rocks. At 

 the time that the Cambrian strata began to be deposited this old 

 "massif" had already been metamorphosed and hardened, as well as 



