158 ROYAL SOCIETY OF CANADA 
may now be seen along the Mount Royal Park drive, near the top of the 
mountain, indicating clearly a differential uplift of beds of this forma- 
tion of at least 500 feet. 
Fossils are everywhere abundant and a list of seventy-eight species 
has been published by the writer in the “Appendix” to Dr. Ells’s report 
on the south-west quarter-sheet map of the Eastern Townships of the 
Province of Quebec (separate), pp. 32-34, 1896. 
Amongst the most characteristic Trenton fossils found at Mont- 
real are the following species :—Glyptocystites Logani, Heterocrinus 
tenuis, Pachydictya acuta, Plectambonites sericea, Prasopora Selwyn, 
Dalmanella testudinaria, Parastrophia hemiplicata, Rafinesquina alter- 
nata, Trenatis Montrealensis, T. terminahs, Lingula riciniformis, 
Rhynchotrema inequivalvis, Cyclonema Montrealense, Bellerophon bilo- 
batus, Conularia Trentonensis, Trochonema umbilicatum, Isotelus gigas, 
Calymena senaria. 
Excellent collections illustrating the extinct fauna of the old Or- 
dovician seas as preserved in the Trenton limestones of Montreal and its 
surroundings, as well as from the various fossiliferous formations of the 
district may be seen in the Peter Redpath museum of McGill Univer- 
sity, most of which were obtained and classified by Sir William Daw- 
son and his students in the departments of geology and paleontology. 
The Utica formation.—The Utica formation consists of dark brown 
and black brittle and bituminous shales, at times indurated or altered, at 
times interstratified with bands of impure limestone especially towards 
the base of that formation and near its conformable contact with the 
Trenton formation. As in numerous other localities throughout Canada 
which the writer has examined, and reported upon the various outcrops 
of this formation, the Utica of Montreal and its vicinity shows no break 
whatever or unconformable contact with the Trenton formation as has 
been pointed out by a number of writers on this question. 
The exact thickness of the Utica in the Montreal district has not 
been ascertained as yet, owing to the isolated and dislocated condition of 
the outcrops, but there can scarcely be less than between 100 and 150 
feet of strata developed. The nearest and best outcrops of this forma- 
tion are seen on St. Helen’s Island, near its western extremity; along 
the St. Lawrence river front, at the Victoria Jubilee bridge, and above 
this point in a westerly direction toward the Lachine Hydraulic Com- 
pany’s works. 
The following are some of the more common and characteristic 
organisms of Utica age :—Reteograptus (?) eucharis, Leptograptus 
flaccidus, Leptobolus insignis, Schizocrania, filosa, Cornulites immaturum, 
Trocholites ammonius, Triarthrus Becki. 

