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The study of the Highwood Mountains was undertaken by a group of men from Harvard University under a grant from the Shaler Memorial Fund of the Department of Geology. The work was under the general direction of Larsen, who, with the assistance of Norman A. Haskell, mapped most of the volcanic rocks. Hurlbut and Griggs worked mostly on the laccoliths, Burgess on the stocks, and Buie on the dikes. The party spent two summers in the field. The laboratory work is far from complete. We cooperated closely in all the work.

recently showed h o w near-flawless to flawless natural amethyst could be separated from synthetic amethyst on the basis of the presence of Brazil twinning i n the natural stones. Whereas Dr. Schmetzer's procedure required a special apparatus, the authors have determined that a standard gemological polariscopeis more than adequate to make the separation i n most cases. Although some synthetic amethyst does show evidence of twinning, in the synthetic stones examined thus far it has taken a form that is distinctly different from the Brazil twinning seen i n most natural amethysts. The presence of certain inclusions as well as the nature of the color zoning seen in natural versus synthetic amethysts is of primary use in making a separation. However, where there are no inclusions or color zoning, the presence of Brazil twinning in the natural amethyst will usually make the distinction.

Tine pr('s('nnt ro'pt)rt coneernns two crystalline masses nneasuring several nnilbimnneters in diameter that occurreol iun tint' sobo'ra of a humann eve and consisted alnnost o'ntiro'lv of lnvdrous calcium sulfate (gypsunnn). Tint' signnificauiee of this finding is twofold: first, tint' unimuss occupied the position of tine connmomn sciernul plaque which has not heretofore beenn nioted to h)e calcific and, secondly, this muppenirs to be tine first time that