Lyman.] -'■" [Jan. 19, 



tern and the other the summit of the Trias, it cannot fail to be regarded 

 as interesting and surprising that the resemblance should be so complete. 

 But for the a priori improbability that a species of seaweed should be so 

 long-lived I should hardly feel justified in giving even a new specific 

 name to the Triassic specimens. Possibly a comparison of more material 

 would show differences not now perceptible, but the peculiar mode of 

 growth and the details of structure seem to be essentially the same. In 

 the Portland sandstones, as in the Umbral shales, the fronds of Dendro- 

 phycus are enrolled in masses thai suggest cabbage heads of large size and 

 rather loose texture, while the mode of subdivision and the character of 

 the final ramifications of the fronds are so like that, with the similarity of 

 the enclosing rock, the specimens from the two localities and horizons 

 are almost undistinguishable." 



It seems clear that the Portland Denirophycus, if viewed without prej- 

 udice, would, like the Belleville and Newark Lepidodendron, strongly 

 indicate the Paleozoic age of the brownstone. 



It is not yet certain, however, whether ihe Portland sandstone and the 

 Newark brownstone are of the same age ; for the Portland beds are near 

 the eastern edge of the so called Mesozoic rocks of Connecticut that have 

 generally easterly dips, so that the beds have sometimes been taken to be 

 near the top of the column, while the Newark beds are no doubt towards 

 the bottom of the so-called Mesozoic of New Jersey. Still the geological 

 structure in Connecticut has not been so thoroughly worked out as to 

 make that position of the Portland beds perfectly sure. Percival's map 

 would seem rather to indicate that they are on the eastern side of a basin ; 

 and Dana (Am. Jour. ScL, 1891, Vol. xlii, p. 44')) says the sandstone at 

 Portland is nearly horizontal, and occasionally the dip is westerly. It 

 seems, then, not impossible that some of the lower, more ancient beds 

 have here come to the surface. It is not yet known, either, how great 

 maybe the total thickness of the Connecticut Mesozoic, so-called ; nor to 

 what parts of the New Jersey and Pennsylvania rocks it may correspond. 

 But the lithological character, as well as the decidedly Paleozoic look of 

 the only determined fossil of the Portland beds, go somewhat strongly to 

 show an Identity in age with the Newark brownstone. 



At any rate the paleontological argument for the Mesozoic age of all 

 parts of the so-called New Red is plainly not so perfect as it has often 

 been supposed to be. 



