256 



DESCRIPTIVE CATALOGUE 



it among them. It is of a purplish-red colour, with numerous dark-green spots 

 disseminated through it. Very fine-grained and compact, with a tolerably smooth 

 fracture. Weathers with a polished, dark brownish-red surface. Magnetic. 



606. Veins of massive epidote, from one to two inches thick, traversing No. 603 

 on the Lake shore, a short distance below the mouth of Riviere des Francaises. 



607. Basaltic trap — bears N. 5° E. Fine granular; homogeneous. Colour, 

 purplish gray ; joints, rusty-coloured. Bears considerable resemblance to No. 601, 

 but differs in colour, and in being slightly amygdaloidal. Contains small nodules 

 of chalcedony. The cells, which are few and small, are filled with a dark olive-green 

 mineral, probably chlorite. The rust in the joints is a dark bright red. Weathers 

 with a smooth, even surface, of a reddish-brown colour. Magnetic. Traversed by 

 No. 603 (?), and traverses No. 588. 



608. Bears N. 15° W. Greenstone — colour, greenish gray; somewhat rough, 

 irregular fracture. Feebly magnetic. Has numerous grains of sulphuret and per- 

 oxide of iron disseminated through it. The green grains and crystals of this rock 

 bear considerable resemblance to hypersthene, but it is so fine-grained, that it can- 

 not be determined by the eye. Traverses No. 588. 



609. Bears E. and W. This specimen is from the grit-beds which lie against an 

 E. and W. basaltic dike. It is the same as No. 359. It is very ferruginous, and 

 full of a green mineral. It is very fine granular, has a nodular fracture, and is 

 feebly magnetic. It has been derived from the dike No. 354. It is, probably, a 

 true volcanic tufa or gritstone, formed by materials deposited either at the time of 

 the eruption, as an overflow, or immediately after that period, from the wearing 

 down of No. 354. No. 359 is very magnetic. 



610. Amygdaloid. The base is reddish gray — very fine granular; and belongs, 

 probably, to the volcanic grit-beds No. 609. It is remarkably cellular — the cells 

 being small, and filled with a soft white mineral, which does not effervesce with 

 acids, probably stilbite (?). It may be called a toadstone. Bears N. 30° E. 



611. Bears E. and W. Traverses No. 610. This is a basaltic rock, like No. 

 609, and is a dike, with a well-defined wall on one side. (The other side could not 

 be examined.) It is red, contains a great deal of iron ; is fine granular, and con- 

 tains a great deal of a zeolitic mineral in small grains and in a few cells, the size of 

 large peas. Has a nodular fracture. It is possible that this rock may be a portion, 

 like the overflow, or may have been a deposit along the margin of the dike during 

 the eruption of No. 354. It is also the same with No. 189, brought from Two 

 Island River. It is difficult to say whether these rocks are due to sedimentary 

 action or not. All analogy, however, seems to indicate that they are deposits of 

 erupted material. Very ferruginous. Feebly magnetic. The iron appears to be 

 mostly in the state of peroxide. Weathers with a smooth, red surface. Contains 

 numerous small scales of mica (?) . 



612. Basalt — colour, dark greenish gray. Very fine granular; homogeneous. 

 It is very compact, and contains no accidental ingredients. 



613. Bears N. 45° E. Greenstone — coarsely crystalline. Colour, greenish gray; 

 the hornblende occasionally in large crystals, with a lustre like black glass ; the 

 felspar, mostly green. This rock, which is massive, bears great resemblance to the 



