218 ROYAL SOCIETY OF CANADA 



dicle valves. This character of the slight fold and sinus along the middle 

 of the shell causes them to resemble C, coronata of the Hamilton Anth 

 which I at first identified them. But close comparison leads to their 

 distinction on ground of the flatter expression in general and to the 

 actually flat, or very slightly arched, brachial valves associated with them 

 in the same rock, showing that the flatness is not due to crushing. The 

 other character, the presence of the crenulations on the hinge area, is 

 not known to occur in any of the Hamilton forms. The fact, mentioned 

 by Clarke,^ that this species Chonetes hudsonicus occurs in the calcareous 

 Oriskany of Becraft mountain is significant, as is also the absence of the 

 species from the Grande Grève limestone. Its abundant expression in 

 the higher Gaspé sandstone (York river beds) where its expression is 

 the same as in the St. Helen's and Côte St. Paul limestone, suggests a 

 connection between the York River and the upper St. Helen's formation. 

 It is with tiie later type, called by Clarke " metaiype gaspensis " that 

 our shell agrees, not with the typical small Becraft species. 



It is further to be noted that Chonetes dilatatus de Konincl', a 

 closely related form, is reported as ranging from the Lower Coblenzian 

 through the Upper Coblenzian and into the typical Middle Devonian 

 with Pleurodictyum and Calceola, so that it is not 'surprising that this 

 species should be found in America in a fauna showing lower as well as 

 upper Devonian affinities. 



9. Chonetes striatissimus, W. & B. 



The second species of Chonetes, found in the St. Helen's lot 2 but 

 absent from the Côte St. Paul faunule, appears to be identical with the 

 form from the Chapman sandstone described as Chonetes striatissimus 

 W. & B. This species is similar in the fineness of surface lineations, 

 general contour and flatness of form to Chonetes canadensis, Billings, 

 but it is uniformily of smaller size ; and the specimens in both the Chap- 

 man sandstone and in the St. Helen's limestone are wider than the typi- 

 cal forms C. canadensis. In the explanation of fig. 7 illustrating that 

 species Billings states that " specimens much broader and shorter pro- 

 portionally occur " ; also in giving dimensions he cites, " 6-31/-2 lines " 

 as size of smallest specimen.^ One of the St. Helen's specimens is ll^/i^ 

 X 18 mm., another 13 x 20 mm. and a fragment from a specimen is a 

 trifle larger than the latter. The average size of the Chapman speci- 

 mens corresponds with these dimensions. The strong median lineation 



1 Clarke, J. M., Early Devouic History of New York and Easteru North 

 America, 1908, p. 238. 



2 Paleozoic Fossils, Vo. II, V\. I, 1S74, p. 17. 



