164 TRANSACTIONS OF THE [MAR. 19, 
EXPLANATION OF THE FIGURE. 
The microdrawing herewith presented shows a portion of the 
rock which does not happen to contain any olivine and has 
rather more feldspar than the average. It brings out the salient 
features of the slide, but cannot pretend to the accuracy of a 
photograph. The needles of apatite are not represented. The 
areas of augite are represented by single series of parallel 
lines; those of hornblende by intersecting lines; those of 
magnetite and ilmenite by solid black; those of feldspar were 
left blank. The dotted areas are those of most marked de- 
composition. Ordinary light. X 115. 
J. F. Kemp, “On Some Camptonite Dikes in the Town of 
Queechee, Vt., near Thetford.” Prof. Kemp gave a general re- 
view of the camptonite dikes of the Green Mountain region, and 
cited in particular several from Queechee Gulf, specimens of 
