Jackson.] 88 [June 17, 



extent. TTie second, and perhaps the most destructive, C. apretus 

 Uhl., has frequently devastated the whole of the region lying west of 

 the Mississippi as far at least as the Rocky Mountains and extending 

 from Texas on the south to the Saskatchawan River on the north. It 

 cannot be an alpine insect, as suggested by Walsh, since the young 

 are readily killed by the cold and it has bred year after year as far 

 south as the State of Texas ; the natural limits of its distribution 

 are as yet unknown. A third species, whether belonging to the same 

 genus or not is still uncertain, has invaded at different times nearly 

 all the country lying within the boundaries of the United States be- 

 tween the Rocky Mountains and the Pacific Ocean. 



Dr. C. T. Jackson communicated a description of the 

 great beds of Apatite, or Phosphate of Lime, which he had 

 recently visited in Canada West, and referred to the speci- 

 mens which he had recently presented to the Cabinet of the 

 Society. 



Near Perth, on the northwest side of Ottey Lake, in the township 

 of North Burgess, the principal quarries now worked are located. 

 From one of these quarries not less than one thousand tons of very 

 pure phosphate of lime, containing from eighty to ninety per cent, 

 of the pure phosphate, had been sent cUiring the past year to England, 

 where it is used in the manufacture of super-phosphate of lime for 

 agriculture, and also in the manufacture of Delft ware, and for the 

 lining of iron kettles with a sort of porcelain. The phosphate of 

 lime is found in a metamorphic rock supposed to be derived chiefly 

 from altered Potsdam Sandstone. The beds run nearly northeast and 

 southwest and are almost vertical in dip. 



Their width varies from a few inches to five or six feet, and the 

 walls of the beds are true and well-defined, indicating persistence in 

 their downward continuity. Indeed, their width, as shown in the 

 mine worked by the English Company, has increased considerably 

 in a depth of thirty feet; and solid blocks of compact or massive 

 phosphate of lane are now extracted, which weigh several tons each. 

 Associated with the phosphate of lime, magnesian mica or phlogo- 

 pite, in regular six-sided prisms, is abundant, and is a constant con- 

 comitant, so much so as to be regarded as the unfailing indication of 

 the apatite, whether crystallized or massive. Calcareous spar of 

 ▼arious colors, orange-yellow and Venettian red, is also found in some 



