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wliicli he found was embedded in tlie marsh, while under it 

 lay strata of loam and clay. The structure of the overlying 

 marsh appeared clearly to establish the idea that the grass 

 had grown at successive periods, at all heights between the 

 top of the stump and the present surface ; and considerations 

 were drawn from the habit and constitution of the marsh 

 grasses to show that nothing but a sinking of the district 

 could account for the facts observed. 



Mr. Mudge resumed his remarks by stating that this ques- 

 tion of subsidence had further proof in a well characterized 

 beaver dam in Gloucester, which had been found with the 

 relics of beaver huts, of the wood laid up for the winter's 

 food, and the tooth marks yet upon it, at a place which is 

 now some two feet below high water mark and of course 

 covered by the tide every day. 



Dr. Henry Perkins of Newburyport said that the geologist 

 might be concerned in knowings that this was a region of 

 earthquakes, averaging one in every two years for these two 

 last centuries and such as might be termed local. He also 

 exhibited a peice of wood, dug up in the vicinity of " Pine 

 Swamp," where it was found ten or twelve feet below the 

 present surface and seemingly in or below the drift forma- 

 tion. 



Mr. Mudge also exhibited to the Institute specimens of 

 precious serpentine, found at " Devils's Den," and some of 

 them in a highly wrought condition, cut into various fancy 

 shapes, as paper weights and the like, from the hand of Mr. 

 Osgood, an artist of Newburyport. This variety was said 

 to be very valuable abroad, and rarely found in Europe. 



Tiie Chair commented upon some of the plants collected 

 during the excursion. 



Mr. F. W. Putnam presented a paper upon " Solanine in 

 the potato," from L. M. Doenbach, of the Lawrence Scien- 

 tific School, which is appended below. Some discussion 

 arose on some of the points treated, and the query proposed 



