R. S. Lull — Life of the Connecticut Trias. 419 



opinion to the opposite extreme, and all the tracks were 

 believed to have been made by dinosaurs. I believe, in most 

 instances, this group of footprints is demonstrably dinosaurian. 

 There are some, however, of which I am not so sure ; but the 

 only final proof of the existence of Triassic birds will be the 

 actual discovery of their remains, for the earliest yet known, 

 Archceopteiyx, of the uppermost middle Jurassic, lived thou- 

 sands of years subsequent to the close of Newark time. If Pro- 

 fessor Osborn is right in supposing the pro-avian to have been 

 arboreal, I should not look for its trail over the sands of the 

 Connecticut valley, and I seriously question whether at so 

 remote a time degenerate terrestrial birds had been evolved. 

 On the other hand, the cursorial origin of birds is conceivable, 

 and if true would be possible within the environment we are 

 discussing. 



Of the mammals, though known apparently in Dromothe- 

 rium and Microconodon from contemporaneous rocks of not 

 very remote geographical locality, we have no record. Their 

 known habitat in the Triassic had a very different climatic 

 and vegetal environment from that of the Connecticut valley ; 

 and this, as in the case of birds, would seem to debar them 

 from the limits of this area. 



Geologically, the history of Newark times was a tremendous 

 drama of which the prologue speaks of the degradation of the 

 ancient hills and the setting of the stage in the form of an 

 extensive though relatively slight depression, with the estab- 

 lishment of the sediment-bearing drainage from the environing 

 upland. Four great acts, of which the first and last were much 

 the longest, succeed each other in time, separated by interacts 

 of appalling grandeur, when vast sheets of molten rock welled 

 from the depths and spread far and wide, blotting out the old 

 and preparing the stage for newer and different players. Of 

 the sequence of the scenes within the acts, the order is not so 

 surely recorded, since they differed in their position in the 

 valley, in the nature of the sediment in which their record is 

 written and in the forms that peopled the stage. The whole 

 drama is incredibly long as we measure time, for each succeed- 

 ing day with its dawning, morning hours, high noon, declining 

 sun, and long night added but the smallest increment to the 

 gradually accumulating sediments, though, as has been said, 

 " Neither time nor space flow evenly," and there were tempes- 

 tuous days whose contribution to the mass made up for the 

 calm passage of those to follow, yet when one thinks of the 

 two and one-half miles of accumulations which these days rep- 

 resent, he can feebly grasp at a realization of the extent of 

 Newark time. 



During the long first act, in the course of which were laid 



