204 Dr. Dawson — Geology of Prince Edward'^s Island. 



and which I have described and figured as Cycadoidea (MantelUa) 

 Abeqiiidensis, the specific name being taken from the old Micmac 

 appellation of Prince Edward Island — Abequid, "Lying in the water," 

 Fragments were also found of coniferous wood belonging to a species 

 of Dadoxylon (Araucaroxylon) allied to D. Keuperianum of Europe, 

 and which I have named D. Edvardianum. The specimens of this 

 tree, which were found by Dr. Harrington, had all been bored with 

 minute cylindrical holes, similar to those now made by the crustacean 

 Limnoria terebrans. These holes being filled with clear calcite, 

 while the wood is of a reddish colour, give the trunks and branches 

 the aspect at first sight of endogenous stems. Branches having the 

 aspect of Knorria were also found, and obscure Sternbergice piths ; 

 and in some of the beds there are numerous cylindrical bodies of 

 various sizes, perhaps stems of fucoids. These Triassic beds have 

 also afforded the jaw of the remarkable reptile described by Dr. 

 Leidy under the name of Bathygnathus borealis, and which seems to 

 have been a Dinosaur, probably allied to those which have left the 

 gigantic trifid tracks on the red sandstone of Connecticut. We were 

 not so fortunate as to find any additional remains of this creature. 



The views which I stated in 1848, in the Journal of the Geological 

 Society, as to the chemical nature and origin of the Triassic red sand- 

 stones of Nova Scotia, appear to be perfectly applicable to those of 

 Prince Edward Island.' They appear to have been deposited in a 

 shallow sea area, not improbably coincident with the Southern Bay 

 of the Gulf of St. Lawrence, limited to the north by the Magdalen 

 Islands and the banks in their vicinity, which represent an old 

 Lower Carboniferous outcrop. Their materials were derived from 

 the waste of red sandstones and marls of the Carboniferous, and 

 have been thrown down with sufficient rapidity to prevent the coat- 

 ing of red oxide of iron from being removed by abrasion or by the 

 chemical action of organic matter. The dolomitic character of some 

 of the coarse limestones may either indicate the occurrence of occa- 

 sional isolated basins and depositions of magnesia from sea-water,^ or 

 may have been connected with the outburst of igneous matter rich in 

 magnesia, like the dolerite of Hog Island, near to which place the 

 beds richest in magnesia were observed. 



On the West coast of Prince Edward Island, and at Gallas Point 

 and Governor's Island in Hillsborough Bay, the beds of the Upper 

 Coal-formation appear rising in low anticlinals from beneath the Trias. 

 As on the neighbouring coast of Nova Scotia, these beds scarcely 

 differ in mineral character from those of the Trias, except in the 

 somewhat darker colour of the red sandstones, and the greater fre- 

 quency of shales, grey sandstones, and concretionary limestones. 

 Their fossils indicate the highest zones of the Carboniferous next to 

 the Permian, corresponding to the " Annularia " and " Eern " zones 

 of Geinitz in Germany. The dips of these Carboniferous beds are 

 not appreciably greater than those of the Trias resting on them, so 

 that we have here the interesting fact of the conformable super- 



' See also Acadian Geology, pp. 24 and 623. 

 ^ As explained by Dr. Sterry Hunt. 



