THE MICROSCOPIC FAUNA OF THE BONAVENTURE 

 CONGLOMERATE 



The Bonaventure conglomerate of the northeastern Atlantic coast 

 sesms to be, as I have often stated, an equivalent and contemporary 

 of the Catskill formation of New York in the sense that in both the 

 deposition of this deposit began before the close of Devonian time 

 and continued over the boundary line as marked in the marine 

 succession into the early Carboniferous. Both seem to be also out- 

 wash gravels and sands. 



This age determination could perhaps not be clearly made on the 

 evidence of either formation. James Hall believed this to be the 

 interpretation of the Catskill formation in New York; the obvious 

 land elevation during the late Devonian of Gaspe with the formation 

 of land ice corroborates this construction and both cases are, in a 

 broad way, supported by the recognized time value of the Old Red 

 sandstone in Britain. The Bonaventure formation is a conglomerate 

 and sandstone lying flat on the almost vertical edges of the early 

 Devonian, Silurian, Ordovician and Cambrian strata and its pebbles 

 . are recognizable fragments from those formations with no incon- 

 siderable mixture- of crystalline blocks from the Gaspe or Lauren tian 

 highlands. 



One often finds in the conglomerate great coral heads of Halysites 

 from the Silurian whose outcrops are known, and the other fossil- 

 iferous pebbles and boulders are a source of constant interest to the 

 student of fossils. The leading constituent of some of the Bonaven- 

 ture beds, however, is flint in the form of jaspers and cherts. For a 

 long time I have suspected these cherts of carrying a- microscopic 

 fauna and am very glad now to present the following evidence of it. 

 Out of a considerable number of sections from these chert pebbles 

 only six have shown the fauna herewith described by Dr Rufus M. 

 Bagg. These few slices of rock not covering in total 3 square inches 

 of surface, have revealed over forty species of Foraminifera, with 

 evidences of Sponges and Radiolaria, and from this one may gain 

 some idea as to the not inconsiderable abundance of these creatures 

 in the rocks out of which these pebbles were washed by the torrents 

 of the late Devonian. 



Doctor Bagg has been disposed to conclude from the very interest- 

 ing evidence he has amassed, that these cherts are of Cambrian or 



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