53 



Correlation. — There is nothing very diagnostic about the fauna occurring in 

 the Meadowvale, but what there is points to a relationship with the Saluda or 

 Whitewater. The Columnaria reef is an important paleontological horizon 

 since it marks the disappearance of the greater part of the Streetsville fauna. 

 Foerste says that Columnaria alveolata, which is so abundant in the Columnaria 

 reef, is most abundant at the base of the Saluda in Ohio. Columnaria calicina, 

 which is more abundant in the reef than at any other horizon, is most abundant 

 in the Saluda, although it occurs in most of the Richmond members in other areas. 

 The Meadowvale member resembles the lower part of the Whitewater section 

 on Manitoulin island from the Gore Bay reef to the Mudge Bay reef, but the 

 upper part of the Whitewater of Manitoulin, with its ostracod fauna and charac- 

 teristic Whitewater species, is missing. 



Comparison of the Credit River Section with the 

 Manitoulin Section 



In comparing the Credit River section with the Manitoulin Island section, 

 many differences will be noticed. In the first place, the upper part of the 

 Whitewater of Manitoulin with its typical ostracod fauna is entirely missing 

 from the Credit river. In the second place, on Manitoulin, the Gore Bay coral 

 reef and the Mudge Bay Stromatocerium reef above are separated by practically 

 unfossiliferous strata, the whole being included in the Whitewater. On the 

 Credit, the Stromatocerium reef is below and is separated from the coral reef 

 by four feet of limestone and shale containing a bryozoan fauna which is dis- 

 tinctly lower than Whitewater in aspect. The Stromatocerium reef itself contains 

 species of bryozoans which are characteristic of the Liberty or even lower horizons. 

 The Stromatocerium reef on the Credit is, therefore, distinctly lower than White- 

 water; in this report it is included in a member which is correlated with the 

 Liberty. In the above discussion, the terms Whitewater and Liberty are based 

 on Foerste's classification of the Richmond formation. 



Many fossils which are abundant in the rocks below the Gore Bay reef on 

 Manitoulin island are entirely missing from the Credit River section, such as 

 Hebertella insculpta, Protarea papillata, Plectambonites sericeus, Rhynchotrema 

 perlamellosa, Rhynchotrema capax, Strophomena nutans, Crania scabiosa, and 

 Strophomena neglecta. 



Apart from the bryozoans, which have not been studied on Manitoulin, 

 the fauna of that island is richer than the fauna of the Credit river. A careful 

 investigation of the Bryozoa of Manitoulin should yield a correspondingly 

 large number of species. 



It would appear from a study of Foerste's report on the Manitoulin section 

 that no rocks equivalent to the Streetsville or Liberty members were laid down 

 on that island. No mention is made of a more calcareous part and the occurrence 

 of numerous bryozoans which are the outstanding features of the Streetsville. 

 The zone of Strophomena sulcata and S. planumbona runs practically as far up 

 as the Gore Bay reef leaving very little room for another member; while on the 

 Credit, the highest occurrence of any of the strophomenoids is 65 feet below the 

 Columnaria reef marking the base of the Meadowvale.' It appears, however, 

 that no study of the Ontario Richmond localities can be satisfactory without 

 a study of the Bryozoa. 



