The Barber mentioned by Tim is John Warner Barber, and the book in question is Connecticut Historical Collections...New Haven, 1836. On page 475 Barber writes: "They dwelt chiefly along the intervale by the river, a part of which intervale is to this day called Indian Field; and several of their burial grounds are yet to be seen in various parts of the town. Their graves are of a circular form, and the persons were buried sitting up, as in a natural position, on the ground." There was no illustration accompanying the description of the graves.
In perusing some issues of the Collections of the Massachusetts Historical Society from the 1790s, I came across this from Jeremy Belknap and Jedidiah Morse, titled "The Report of a Committee of the Board of Correspondents of the Scots Society for Propigating Christian Knowledge, who visited the Oneida and Mohekunuh Indians in 1796." The date of the original publication was 1798, and this is found on pages 14 and 15: "He regarded the Oneida Stone as a proper emblem or representative of the divinity whom he worshipped. This stone we saw. It is or a rude, unwrought shape, rather inclining to cylindrical, and of more than a hundred pounds weight. It bears no resemblance to any of the stones which are found in that country. From whence it was originally brought, no one can tell. The tradition is that it follows the nation on their removals. From it the name of the nation is derived, for Oneida signifies the upright stone. When it was set up in the crotch of a tree, the people were supposed invincible. It is now placed in an upright position on the earth, at the door of the old man's house. A stout man can carry this stone abourt 40 or 50 rods, without resting; and this is the manner in which it may be said (with the help of a little priestcraft) to follow them in their removals." The authors are certainly referring to a godstone or Manitou stone.