Penrose.] APATITES OF CANADA. 41 
of life as the formation of crystals of quartz or of hematite. 1 Prof 
J. W. Dawson, 2 on the other hand, thinks the Canada apatites are of 
animal origin, and bases his belief on the presence of eozoon and of 
graphite in the associated beds and of the fluoride of lime in the apa- 
tite. He s;iys: "The probability of the animal origin of the Lauren- 
tiau apatite is, perhaps, further strengthened by the prevalence of ani- 
mals with phosphatic crusts and skeletons in the primordial age, giving 
a presumption that, in the still earlier Laureutiau, a similar preference 
for phosphatic matter may have existed, and, perhaps, may have ex- 
tended to still lower forms of life, just as, in more modern times, the 
appropriation of phosphate of lime by the higher animals, for their 
bones, seems to have been accompanied by a diminution of its use in 
animals of lower grade." 3 Messrs. Brogger and Eeusch, 4 in their de- 
scription of the Norwegian apatites, think that they are of purely erup- 
tive origin. 
1 Chem. and Geol. Essays, 1875, p. 311. 
2 Quart. Jour. Geol. Soc. London, vol. 32, 1876, p. 290. 
3 The reader should note the fact that since the admirable researches of Mobius it 
is doubtful whether eozoon be of organic origin. — N. S. S. 
4 Zeitschr. Deutsch. geol. Gesell., Berlin, vol. 27, 1875. 
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