202 Canadian Record of Science. 



logical relationship, however, constituting as they do a 

 distinct and remarkable petrographical province, such. 

 a name is required. I propose to call them the Mon- 

 teregian Hills, deriving their name from Mount Royal 

 ( " Mons Regius " ), which may be taken as their type, 

 being as it is the best-known member of the group. 



There are certain other hills which have been consid- 

 ered by former workers in the geology of this district to 

 belong to this group. Thus Logan thought that Rigaud 

 Mountain, situated near the margin of the plain, by the 

 river Ottawa, about forty miles west of Mount Royal, was 

 " probably connected with " the series. 1 Ells'* also in- 

 cluded Mount Calvaire, a large, low mass which rises from 

 the plain immediately to the north of the Lake of Two 

 Mountains, near the junction of the Ottawa and the St. 

 Lawrence. 



Ells also refers to " the hills on the west side of 

 Memphremagog lake and to the northeast toward the 

 Chaudiere river and beyond " as bearing a marked resem- 

 blance to the rocks of Mount Royal, Yamaska, etc., and as 

 probably being of the same age. 3 



In a careful study of Rigaud mountain, recently com- 

 pleted by Mr. Leroy, 4 of this university, it is shown that 

 the rocks constituting this mountain are different in 

 character from those of the Monteregian hills, being com- 

 posed of a reddish hornblende syenite and a quartz bear- 

 ing porphyry. These rocks, however, were found to be 

 identical, in character and composition with a great area 

 of syenite, cut by porphyry, mentioned by Logan as 

 occupying some forty square miles in the townships of 

 Chatham and Grenville on the margin of the Lauren tian 



Montagues included these hills as one of his systems, under the name of the " Systeme 

 de Montreal." See Prestwich, Geology, Chemical, Physical and Stati graphical, Vol I, 

 ].. 294. 



1 ecology of Canada, 1863, p. 9. 



2 ".Report on a portion of the Province of Quebec," Ann. Rept. Geol. Surv. of 

 Canada, Vol. VII, Part J, 1896. 



3 Eastern Townships Map (Montreal Sheet), Ann, Rept. Geol. Surv. of Canada, 

 Vol. V It. Pari J. 



4 Bull, of the American Geological Society, Vol, XII, 1901. 



