352 PALEOZOIC ROCKS OF THE HUDSOX BAY EEGIOX 



Pterygametopus sp. 

 Leperditia sp. 



CORRELATIOX OF THE SHAMMATTAWA LIMESTOyE 



The fossils as well as the lithology of the Shammattawa limestone are 

 remarkably similar to those of the Stony Mountain (Upper Ordovician) 

 limestone in the Lake Winnipeg region and correspond also with those 

 of the Bighorn dolomite in Wyoming and those of the Montoya limestone 

 of Xew Mexico. The rocks at all of these localities consist of gray to 

 yellowish, subscrystalline limestone, with layers and mottled areas of 

 yellowish brown dolomite. The more common species of fossils occurring 

 in the Shammattawa limestone are shown in the following list of species. 

 In this list the species having a cross after the name are reported from 

 the Stony Mountain limestone of the Lake Winnipeg region, and those 

 having a cross in front of the name occur also in the Bighorn dolomite 

 of Wyoming. 



List of the more common Fossils from the Sharnmattaica Limestone 



StrepteJasrna latuscula.— 

 + StrepteJas7na latuscida var. triloliata.— 

 -V Streptelmasma sp. 

 + CoJumnaria alveolata.— 

 -r Columnari-a (PaleophyUum ) stokesi.— 

 + CalapcECia can<ide)hsis.-\- 

 + Paleofavosites asper.-{- 

 -\- Hal y sites gracilis. n- 



HaUopora sp. 



Ptilodictya sp.— 



Dino'bo'lus sp.— 



Rafitiesquina cf. aIternata.-\- 

 4- Strophomena fluctuosa.— 



Strophomena sp. 

 -i- Dinorthis aff. sudquadrata 4- (witli coarse strise'). 



PlatystropJiia near crassa. 

 + Rhynchotrema aff. capax.-^ 

 + HoJopea cf. e^rcelsa. 



MacJuri7ia sp. 

 + Trochonayna cf. umlilicatum.-^ 



Eormotoyna sp. 



Raphistoma sp. 



Ascocefas sp. 



Cyrtoceras sp. 



Bumastus sp. 



The fossils in the foregoing list indicate the Eichmond age of the strata 

 from which they came. The close similarity' of this fauna in such widely 



