No. 3. J DAWSON — PHOSPHATES OF CANADA. 163 



Laurentian period, but which may also be of interest to British 

 geologists in connexion with the facts recently published in the 

 'Journal' of this Society in relation to the similar deposits 

 found in the Cambrian and Silurian of Wales.* 



In the Lower Silurian and Cambrian rocks of Canada, phos- 

 phatic deposits occur in many localities, though apparently not 

 of sufficient extent to compete successfully for commercial pur- 

 poses with the rich Laurentian beds and veins of crystalline 

 apatite. 



In the Chazy formation, at Alumette Island, and also at Gren- 

 ville, Hawkesbury, and Lochiel, dark-coloured phosphatic nodules 

 abound. They hold fragments of Lingulce, which also occur in 

 the containing beds. They also contain grains of sand, and, 

 when heated, emit an ammoniacal odour. They are regarded 

 by Sir W. Logan and Dr. Hunt as coprolitic, and are said to 

 consist of " a paste of comminuted fragments of Lingulce, evi- 

 dently the food of the animals from which the coprolites were 

 derived." f It has also been suggested that these animals may 

 have been some of the larger species of Trilobites. In the same 

 formation, at some of the above places, phosphatic matter is seen 

 to fill the moulds of shells of Pleurotomaria and Holopea. 



In the Graptolite shales of the Quebec group, at Point Levis, 

 similar nodules occur ; and they are found at Riviere Ouelle, 

 Kamouraska, and elsewhere on the Lower St. Lawrence, in lime- 

 stones and limestone conglomerates of the Lower Potsdam group 

 which is probably only a little above the horizon of the Menevian 

 or Acadiau series. In these beds there are also small phosphatic 

 tubes with thick walls, which have been compared to the sup- 

 posed worm tubes of the genus Scrpulites.% 



The Acadian or Menevian group, as developed near St. John, 

 New Brunswick, contains layers of calcareous sandstone blackened 

 with phosphatic matter, which can be seen, under the lens, to 

 consist entirely of shells of Lingulce, often entire, and lying close 

 together in the plane of the deposit, of which in some thin layers 

 they appear to constitute the principal part. § Mr. Matthew in- 

 forms me that these layers belong to the upper part of the forma- 



* Davies & Hicks in Quart. Journ. Geol. Soc, August, 1875. 

 f Geology of Canada, p. 125. 



t Geology of Canada, p. 259 ; Kichardson's Report, 1869. 

 § Bailey and Matthew, " Geology of New Brunswick," Geol. Survey 

 Reports. 



