250 Prof. Rogers's Address before the 



stration, and from a few isolated phenomena casually presented to him, 

 developes to the view of all after generations an eternal truth, then as- 

 suredly must Prof. Hitchcock be regarded as the only scientific discov- 

 erer of the origin of these curious and instructive foot-prints. The con- 

 scientious wish to acknowledge the claim of Dr. Deane as a suggester 

 of the ornithichnite character of these impressions, has led some of those 

 who have lately reviewed this subject, to do, I think, an unintentional in- 

 justice to the well-earned and far more ample claims of Prof. Hitchcock. 



In speculating upon the circumstances connected with the deposition 

 of the red sandstone, Prof. Hitchcock supposes the Connecticut forma- 

 tion to be the sediment of an extensive tidal estuary, upon the low and 

 muddy beach of which the various birds whose footsteps he has descri- 

 bed, were in the habit of walking and wading at low tide in pursuit of 

 their prey — their foot-prints being covered with a thin layer of silt, 

 probably at each reflux of the waters. Some of these birds, rivaling 

 in size the recently extinct gigantic Dinornis of New Zealand, whose 

 height is computed by Prof Owen to have been more than ten feet, and 

 frequenting in numerous flocks those lonely shores of the great Connec- 

 ticut bay, must have imparted a strange aspect to the landscape. 



Prof. Mather conceives that in this early mesozoic age, the Blue 

 Ridge and Green Mountain chains having been previously elevated, and 

 much of the country to the eastward being still submerged, " the cur- 

 rent which we call the Gulf Stream must have flowed along the eastern 

 coast of this part of the continent where the red sandstone formation 

 now extends ;" and to this, and to a supposed polar current from the 

 northeast, he ascribes its deposition, attributing the present dip of the 

 beds to the overlapping of the one current upon the other. To sustain 

 this hypothesis, it would be necessary to show that it is not at variance 

 with the inferences to be drawn from the bird-tracks and other data, 

 which I cannot but consider to indicate, not an open sea, but the exist- 

 ence of two confined tidal estuaries. 



The strata which constitute the next link in our broken succession of 

 mesozoic formations, are the coal rocks of Eastern Virginia. The por- 

 tion of these productive in coal, occupies a basin in the vicinity of 

 Richmond, about thirty miles long, and eight miles wide in its centre, 

 extending from the Appomattox across the James river to near Chicka- 

 hominy. Another rather higher and unproductive mass is spread irreg- 

 ularly in a narrow belt east of the former, from the Potomac to the 

 James river. 



Both of these deposits repose immediately on gneissoid and granitic 

 rocks, and consist for the most part of coarse grits composed of the 



