4 NOTES ON CONCRETIONS 



They appear to be composed of cherty argillite, and are slightly 

 calcareous, and some when broken through the centre show 

 concentric layers, chiefly of pyrites. No distinct radiating 

 structure, and no nuclei were seen in any of the specimens broken. 



6. In the Devonian rocks of Kettle Point, in Bosanquet, on 

 Lake Huron, forms similar to the foregoing in outward appear- 

 ance exhibit different internal structure. They are described in 

 the Geology of Canada, 1863, p. p. 387-88, as : " Peculiar spher- 

 oidal concretions whose fancied resemblance to inverted kettles 

 has probably given its name to the point. They vary in size 

 from three inches to as many feet, and are sometimes nearly 

 spherical, and others sometimes flattened, generally on the under 

 side. Occasionally a smaller spheroidal mass is implanted on 

 the top of a larger one. These concretions are readily broken, 

 and are then seen to be composed of brown crystalline carbonate 

 of lime, which is confusedly aggregated in the centre, and some- 

 times contains blende. Around this are arranged slender 

 prismatic crystals which extend from the nucleus to the circum- 

 ference ; the whole having a radiating columnar structure, which, 

 not less than the terminations of the prisms, at the surface of 

 the spheroidal masses, gives them very much the aspect of 

 fossil corals " 



7. The Upper Devonian fish and plant bearing beds of 

 Scaumenac Bay, New Brunswick, are prolific in fossiliferous con- 

 cretions, which are composed of calcareo-arenaceous rock, and 

 take various forms according to the shape of the nucleus, which 

 is often so well preserved that every bone can be seen. One of 

 these concretions obtained by A. H. Foord measures over twenty- 

 one inches in length, and contains the skeleton of a fish almost 

 as long. It is Chirolepis Canadensis (Whiteaves). In other 

 concretions from this locality the writer and Mr. A. H. Foord 

 found : Glyptolepis microlepidotus (Agassiz), Phaneropleuron 

 curium, Pterichthys Canadensis (Whiteaves), Eusthenopteron 

 Foordi, etc. 



In the coal bearing rocks s of Skidegate Inlet of the Queen 

 Charlotte Islands, concretionary nodules are found, in which 



