360 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 7=; 



the section, and it is possible that a block of lime- 

 stone found in the bed of Upper Moose River, 6 miles 

 (9.6 km.) southeast of Moose Pass, may have been 

 derived from the south-eastern extension of these 

 limestones, as the fossils appear to be of Upper Cam- 

 brian age, including (6ir) : 



Lingulella. sp. 



Lingulepis sp. 



Hyolithes sp. 



Kingstonia sp. 



Lynx Formation 



Feet Meters 

 I. Thin-bedded, bluish-gray limestones, with interbedded 



bands of light gray shale, and at the base a band of 

 about 200 feet (60.9 m.) of gray, greenish, and reddish- 

 brown shale 3,500 ^ 1,066.8 



A thorough study of the lower 1,000 feet (304.8 m.) 

 of the Lynx formation may furnish data that will 

 result in correlating the lower portion of the shales 

 and limestones with the Arctomys formation of the 

 Glacier Lake section. Wherever found, these arena- 

 ceous parti-colored shales and shallow-water deposits 

 mark the boundary between the Middle and Upper 

 Cambrian. 

 Fauna. — No fossils were found in situ in the Lynx forma- 

 tion in 1912, but in 1913, after the pubHcation of my 

 paper on the Robson section, I found at two horizons 

 (6iy), which is about 500 feet (152.4 m.) below 

 the Kainclla faunule of (6iq) and (6iz), and about 

 900 feet (274.3 m-) below (6iq), a few fragments 

 which unfortunately represent entirely new species. 



The difficulty of getting a section of the Upper 

 Cambrian strata on Chushina Ridge and Lynx Moun- 

 tain is well shown on pis. 105 and 107. Not only are 

 the strata concealed by snow and ice, but they are 

 broken by cliffs and possibly by faults that are more 

 or less concealed by small glaciers. On this account, 

 the section on lyatunga Mountain measured by L. D. 

 Burling is repeated on page 366. 



MIDDLE CAMBRIAN 

 Titkana Formation * 



I. Massive-bedded, bluish-gray limestone in thin layers, 

 interbedded with gray, siliceous, buff-weathering lime- 

 stone that occurs in bands 50 to 100 feet (15.2 to 

 30.5 m.) thick 2,200 670.6 



^This is 1,400 feet (426.7 m.) greater than the estimate made in 1912. 

 See p. 245. The lower portion of this section was compared with the lower 

 part of the Bosworth formation by me in 1913 and referred to as suggesting 

 land deposits. (Problems of American Geology. The Cambrian and its Prob- 

 lems, December, 1913, Yale Univ. Press, 1915, p. 186.) 



