THE HAMILTON ASSOCIATION. 33 



your notice a few specimens of all three ; some of them are in 

 rather poor preservation. 



Sir Wm. Dawson does not think Licrophycus represents a plant 

 at all. He. supposes it to be the trail of a crustacean or other 

 creature to or from its burrow. There are a few other forms, 

 possibly organic, but for the present it may be better to put them 

 aside as doubtful. , 



In the meantime we may in ascending order pursue our investi- 

 gations into the Upper Red Clinton Band, which probably is the 

 equivalent of the Iron Band of the New York State Survey. How- 

 ever, it limestones there rest on the Iron Band, as stated perhaps 

 incorrectly, our upper green shales must be absent altogether, or a 

 second ferruginous bed, which is not seen at Hamilton, caps the series. 

 Dr. Hall, of Albany, however, informs me that such is the case. 

 The plants of the Clinton Iron Ban'd, widely differ from true fucoids. 

 They present no internal structure like land plants, but it is rather 

 singular that they are frequently found erect, and it is necessary to 

 break the flags across, not split them, in order to get good specimens. 

 Indeed, they seem to be species of marsh plants that grew on the 

 mudtiy soil, and the earthy iron ore itself is perhaps due to their 

 presence. Dana remarks that " iron could never have been deposited 

 in an open sea. Clayey iron deposits do not accumulate under such 

 circumstances ; they are proof of extensive marshes, therefore of 

 land neaj the level." f^. 



That the tide had access occasionally is evident from the un- 

 doubted presence of such shells as Lingula and others, which buried 

 themselves ^n muddy sediment between tides, perhaps like the 

 modern Cardium (Cockle). 



A few years ago it was found necessary to remove a large quan- 

 tity of stone and shale which had fallen from the cliff behind the 

 Reservoir, near the residence of Judge Robertson. On examining 

 the material which had been emptied down the hill slope beneath 

 the Jolley Cut road, I was surprised to find in the debris a fragment 

 converted into iron, resembling in external appearance a coral 

 Zaphrentis or Chsiophyllum. Sir Wm. Dawson, however, thought 

 it bore a nearer resemblance to a plant. I have never known a case 

 where a coral has been changed into iron, but I had in my possession 

 a land plant from the English carboniferous rocks fossilized precisely 

 in the same manner. I have no doubt our great fossil botanist was 

 quite correct in his views respecting it. 



