REPORT OF THE CHIEF ASTRONOMER 513 



SESSIONAL PAPER No. 25a 



Top, erosion surface. 



a. 200 feet (rough estimate). — Shale and sandstone. 



b. 600 " Massive light gray to whitish, crystalline limestone with 



numerous crinoidal fragments in places. 



c. 90 " Rhale, sandstone and grit. 



d. 110-h" Massive light gray limestone with large crinoid stems 



and same fossils as member e. 



e. 300^" Dark gray shale with fossils, No. 104. 

 /. 100 " Massive, hard sandstone. 



g- 1,400 " (rough estimate). — Hard sandstone, red and black shale, grit and thin 



bands of fine conglomerate. 

 h. 800 " Hard massive gray sandstone with gritty layers. 



Base hidden under talus of Tamihy creek canyon. 



Dr. Girty found the fossils of No. 104 to belong to the following species : — 



Pentremites sp. 



Platycrinus sp. 



Fenestella aff. perminiuta Ulrich. 



Fenestella sp. 



Pinnatopora sp. 



Polypora cf. submarginjata Meek. 



Chonetes sp. 



Productus semireticuHatus Martin. 



Spirif erina sp. 



Hustedia aff. compressa Meek. 



Section IV. 



At Thurston's ranch nearly opposite the mouth of Slesse creek, from there 

 northward up the mountain-side, and also westward along the Chilliwack river, 

 a very rough section has been run through the dense brush. No great confidence 

 is felt in the result, for there is a possibility that strike faults ' or other 

 unsuspected structural complications have repeated members of the series, or, 

 on the other hand, have faulted some of them out of sight. Attention was first 

 called to this particular part of the river section by the discovery of- abundant 

 crinoid stems in a heavy limestone cropping out just north of the ranch. This 

 limestone seems to be at least 400 feet thick, though its base is concealed; it 

 probably corresponds to member e in Section I. Northward from this outcrop 

 the succession was crudely determined to be : — 



Top of section, not well exposed. 



a. 125 + feet. — Dark gray and black shale. 



b. 150 " Coarse agglomerate composed of dark andesitic or basaltic fragments 



of large size together with other large fragments of limestone. 



c . 90rfc " Typical pillow-lava, basaltic ; pillows round, up to three feet in diameter, 



with the spaces between them filled with cherty matter. 



d. 75 " Brown and gray shale. 



c. 300 " Light gray, massive limestone. 

 /. 50 " Brownish shale. 



g. 150 " Coarse feldspathic sandstone with conglomerate lenses. 

 h. 400+ " Light gray, crystalline, massive limestone with large crinoidal stems 

 quite abundant. 



1,340+ feet. 



Base concealed. 



25a— vol. ii— 33 



