96 RELICS OF PRIiMEVAL LIFE 



matter similar to that in more modern bituminous 

 shales and bituminous and oil-bearing limestones. 

 The beds of graphite near St. John, some of those 

 in the gneiss at Ticonderoga in New York, and at 

 Lochaber and Buckingham and elsewhere in Canada, 

 are so pure and regular that one might fairly com- 

 pare them with the graphitic coal of Rhode Island. 

 These instances, however, are exceptional, and the 

 greater part of the disseminated and vein graphite 

 might rather be compared in its mode of occur- 

 rence to the bituminous matter in bituminous shales 

 and limestones. 



" We may compare the disseminated graphite to 

 that which we find in those districts of Canada in 

 which Silurian and Devonian bituminous shales and 

 limestones have been metamorphosed and converted 

 into graphitic rocks not dissimilar to those in the 

 less altered portions of the Laurentian.^ In like 

 manner it seems probable that the numerous reticu- 

 lating veins of graphite may have been formed by 

 the segregation of bituminous matter into fissures 

 and planes of least resistance, in the manner in 



^ Granby, Melbourne, Owl's Head, etc., "Geology of 

 Canada," 1863, p. 599. 



