Geology and Mineralogy. 147 
and the Fort Pierre and Fox Hills Groups the Upper White 
Chalk, and, possibly, also the Maestricht beds of Europe. 
3. Shower of Volcanic dust over Scandinavia.—In March of 
1875, according to A. E, Nordenskidéld, a shower of volcanic dust 
fell widely over Sweden and still more abundantly over Norway, 
making a layer over some places a quarter of an inch thick. The 
dust was pumice-like in constitution. It is traced to Iceland. 
On the 30th of March the winds were northwest and west. 
eruption began in Iceland in the preceding December, from nu- 
merous craters in the interior, and the most abundant ash-shower 
occurred over the island on the 29th of March, covering so 
astures six inches deep; and if the ashes of the same shower 
Mobius, of Kiel, in 1874, on a coral reef off Mauritius, of an incrust- 
ing foraminifer, which, in mode of growth and peculiarities of 
Structure, approaches rather closely the Eozoon. ; 
Dr. Dawson states that Mr. Richardson has found at Chibogo- 
mon, Canada, in a great bed of olive-green serpentine (a kind an- 
aly zed by Hunt) a specimen of tabulate coral, having many of its 
thin-walled hexagonal cells filled with serpentine, while others 
ti 
r. Dawson has described ar. Jour, Geol. Soc., Feb., 1876) 
‘pecimens of eng nip ce from Cote St. Pierre, in the 
