TRANSACTIONS OF THE SECTIONS. IJjT 



sources of the Red River of Winnipeg to the Arctic Sea, between the crystalline 

 lacustrine zone on its east, and the cretaceous and tertiary prairies on its west. 



The Chippewayan basin, more vaguely known, may be defined, provisionally, as 

 coextensive with the Rocky Mountains and Humboldt Mountains of the Utah 

 Desert, and as including wide tracts surrounding the sources of the Rio-Colorado 

 of California, palaeozoic rocks being developed on a stupendous scale between the 

 Rocky Mountains and the Salt Deserts of Utah and the Columbia River. It would 

 seem from paleeontologic evidence, that each chief division of palaeozoic time, except 

 the Permian, is represented within each of these vast tracts or basins; and there appear 

 good reasons for inferring that many of the Appalachian formations, modified in com- 

 position and fossils, extend into both the other areas. 



The Hudson Bay Palceozoic Basin, lying north of the crystalline plateau, skirting 

 the valley of rhe St. Lawrence and its lakes, is of much more limited extent than 

 the main continental area. The zone of metamorphic rocks separating the two, after 

 running from Labrador to the head of Lake Superior, deflects to the north-west and 

 ranges in that direction 1500 miles to the Arctic Sea. Hitherto no strata of Cambrian 

 or Lower Silurian age have been detected within the basin thus enclosed. 



Appalachian Formations. — The palaeozoic strata of the Appalachian basin consti- 

 tute fifteen series or natural groups, individualized by distinctive organic species and 

 by their mineral composition. Some of these blend together both in their fossils and 

 their materials more than others, and it becomes important to ascertain their relative 

 degrees of affinity. Objecting to a geographical nomenclature as inapplicable to 

 formations so very widely distributed, and on the same ground of their inconstancy, to 

 the plan of naming them from prevailing local fossil or mineral features, titles have been 

 applied to them based on the consideration of their relative age, using a series of terms 

 significant of the different natural periods of the day as metaphorically expressing the 

 relative ages of the formations. These Appalachian rocks of North America are 

 therefore here named Primal, Auroral, Matinal, Levant, Surgent, Scalent, Premeri- 

 dian, Meridian, Pomeridian, Cadent, Vergent, Ponent, Vespertine, Umbral and Serai ; 

 the deposits, that is to say, of the dawn, daybreak, morning, sunrise, mounting- 

 day, climbing- day, forenoon, noon, afternoon, declining day, sinking day, sunset, 

 evening, dusk and nightfall. 



[The communication, of which this is an abstract, contains in this place a tabular 

 view of these ^<ee« series of formations, with their synonyms and nearest equivalents 

 among the European strata ; also their lithological characters, their more character- 

 istic organic remains, and the nature and relative magnitude of the physical and 

 ontological breaks which separate them ; but it is too voluminous to be inserted 

 here.] 



This vast succession of strata admits of a somewhat natural classification into four 

 assemblages, partially representing the Cambrian, Silurian, Devonian, and Carboni- 

 ferous series of European geologists, but the relative values of these groups are by no 

 means the same as the European, and it is doubtful if some of them can be strictly coor- 

 dinated. One main object of this essay is to indicate the proportionate value of the 

 differential elements which divide the fifteen members of the system, and bring these 

 into relationship with the palseontological breaks upon the recognition of which the 

 palaeozoic rocks of Europe have received their present classification. Attention will 

 be first directed to the stratigraphical phaenomena, and then to the palaeontological ; 

 but some preliminary suggestions will be offered respecting the inferences to be de- 

 duced from the conditions of superposition of strata. 



It must be conceded that every over-resting sheet or current of water has left some 

 permanent monument of its presence, and therefore wherever between two strata or 

 ancient surfaces known to have been produced in periods separated by some interval 

 of time nothing sedimentary intervenes, we must assume the vacuous space to have 

 been dry land. It is not supposable that water, endowed as it is with a power of 

 suspending and transporting sedimentary matter into the very middle of the ocean, 

 and there and everywhere teeming with animal and vegetable organisms, could have 

 rested over any surface without leaving an indelible record behind it. Until it can 

 be proved that some one formation has been thoroughly swept away from a wide 

 area where it was deposited, we are not entitled by rules of sound reasoning to infer 

 that such have existed. 



18S6. 12 



