78 COXTRIBUTIOXS To CANADIAN PAL/EONTOLOGT. 



E. FEOM THE "LOWER DAEK SHALES ■ OF DE. DAWSON'S 



EEPOET. 



These are obviously (".'I'etacMous but their exact horizon in the upjjer 

 division of that formation has not yet been a^certain&l with much 

 certainty. 



Of the eleven sjic-cie- of f■o^sils which have so far been collected from 

 them, seven oi- eight seem to be identical with fornix that are elsewhere 

 i-e.i;-arded a-, chararteri^tic of the Fort Pierre or Fox Hills Group, 

 but the presence in these shales of Scajiln'tes Warreni, var. Wijoming- 

 fiiisis, and possibly of Ostrea congesta, may indicate that they occupj' a 

 slightly lower position in the series. 



Dr. Dawson statc--^ that oq the :\Iilk Eiver, at the mouth of Pa-kow- 

 ki Coulee these shale- undoubtedly and dii-cctly underlie the yellowish 

 beds of the Bellv Eiver Series. 



LAMELLIBEAXCHIATA. 



Ostrea coN(iESTA. Conrad. 



0.<irrn conijet^to , Conrad. 1S43. Nicollet's Rep. of Exiil. in the ^'ortliwest, p. 107. 

 " " Hall and ISIeek. 18-')4. ^leiii. Am. Ac. Arts and Sc, Boston, vol. 



VIII. (11. s.}, p. 405. 

 " " Meek and Hayden. 1850. Proc Ar. ^^at. Sc Phil., p. 2SiJ. 



Hall. ls,56. Paritic It. R. Rt-iiort,, vol. III., p. lOfi, pi. 1, tig. 11. 



Meek. 1S7(;. Rep. I' S, <Teol. Surv. Terr., vol IX., p. 13, pi. 9, 



tigs. 1, a, b, c, d,e, f. 



Eocky Spi-ini;' Eidge. near MacLeod Benton Ti'ail, G. M. Dawson. 

 1881: a few exfoliated and badly preserved vak'e^ on two small slabs 

 of limestone. 



West flank of West Butte, Montana, in the Sweet Grass Hills and 

 close to the international boundary line, G. .M. Dawson, 1881 : one 

 perfect uiider valve, attached by it-, whole lower suidace to a fragment 

 of the outer lav'er of the te.st of a laruc Inoi'erinims. 



The-c specimens are for the most part loo impeid'ect to be identified 

 with much certainty, tliMugdi they agi-ee verj- well with MeekV de-ci-ifi- 



"■(ie'A. and Xat. Ili-t. .Surr. C.in..a;i. Rrp- Pr..-re-i. ISSj-V',--).— E,_.|,.,rt on the Region in the 

 ViciiiitN of the Bow .iiid Belly Riv.-v-, X. W. T , p. 117c. 



