226 THE CANADIAN NATURALIST. " [Vol. 



VI. 



discharge lava of very unlike characters. This fact was then com- 

 pared with the different characters of the various mountains of 

 erupted rock around us. Thus Beloeil was in great part, at least, 

 a micaceous diorite ; Monnoir a diorite of another type ; Yamaska 

 presents two kinds of erupted rock, unlike either of these. Mon- 

 tarville, though in a great part a dolerite consisting of a coarse 

 grained mixture of black pyroxene with white feldspar, shows in 

 the hill rising from the lake just behind the manor-house, a rock 

 of very different type, consisting of a coarsely crystalline mixture 

 of daik green pyroxene with a considerable amount of amber- 

 brown olivine or chrysolite, which in other parts of the mass is 

 associated with a white feldspar and with black pyroxene. The 

 various rocks of these different mountains have been described in 

 detail by the speaker in " The Greology of Canada," He concluded 

 by saying that the stratified rocks around tin mountain have a 

 history not less beautiful and curious than that of erupted rocks, 

 and would now be described by one far more competent to the 

 task than himself — Principal Dawson. 



Dr. Hunt concluded his remarks amid much applause. 



Principal Da^vson then said that ancient though the volcanos 

 referred to by the last speaker were, there were still more ancient 

 facts represented by some of the specimens which had been collec- 

 ted. The fossil shells and crinoids represented by specimens 

 which he exhibited, showed the evidences of an ancient Lower Si- 

 lurian sea, which once overspread all the plain of Canada, and in 

 which flourished multitudes of curious creatures now extinct. He 

 particularly referred to the Crinoids or stone lilies, some curious 

 specimens of which had been collected. He then thanked the com- 

 pany for their presence, referred to the fact that the excursion had 

 been honored by the presence of the Director of the Geological 

 Survey, and by many of the elite of the citizens of Montreal, and 

 to the kindness of the lady of the manor, who had so liberally 

 o-iven them the use of her grounds ; and cordially invited all who 

 might have been interested in the day's works to connect them- 

 selves with the Society. The President was warmly applauded. 



A little after 4 o'clock the conveyances were again in requisi- 

 tion, and the party returned to Boucherville Station, and arrived 

 at Montreal about 7 p.m. 



J. F. W. 



