LwiiLiAMs] FOSSIL FAUNAS OF THE ST. HELEN'S BR'ECCIAS 209 



ated from No. 2 hy a wide dyke, the rock in this mass seems to have been 

 all hoken up and receme^ited. I have sent a weathered surface which 

 shows the broken up character, the rock at this point is much harder 

 than No. 2, and is not so fossiliferoiis; at this point I have collected 

 Favosites and Zaphentis but not from Nos. 1 or 2. 



As to the toeight I have no means of tceighing it, bnt think there 

 are about %, of a ton. 



Yours truly, 



E. Ardley. 



A brief statement of the conclusions I sent to Prof. Adams in regard 

 to the age of the St. Helen's Island breccias is given in a paper on the 

 geology of St. Helen's Island by A. W. Nolan and J. D. Dixon i as fol- 

 lows : After de'scribing the breccias and after referring to the two in- 

 cluded limestone masses the authors say: — "These limestone occurrences 

 were opened up^ by blasting, the material obtained being forivarded to 

 Dr. II. S. Williams, of Yale University, ivlio has made a careful study 

 of the fauna, ivhicli they contain and through his courtesy we are en- 

 abled to state the age of the two limestones. The larger area is of Lower 

 Oriskany ng& \{Early Devonian), as expressed in Western Ontario and 

 Virginia, while the smaller area is Lower llelderberg {upper Silurian), 

 and corresponds to the upper Pentamerous zone of Eastern New York. 

 It is of peculiar interest to find remnants of these tivo formations in the 

 present locality; inasmuch, as they have not been found in situ else^ 

 where in Western Quebec. The occurrences indicate an extension of the 

 tipper Silurian and Early Devonian sects as far north as Montreal." 

 (P. 57.)2 



As no report of the ' foundation for this conclusion communicated 

 to Professor Adams in my letter of May 16, 1902, has been published, 

 it may be of interest here to state that the evidence upon which Oriskany 

 age of the limestones (Lot 1) was based were the presence of: Spirifer 

 arenosus, Cyrtina rostrata and Metaplasia pyxidata. 



This limestone is the one from which came the mucronate species 

 of Spirifer (which has been frequently referred to as very similar to 

 long winged specimens of Spirifer pennatus, Atwater, of the Hamilton, 

 and was identified as Spirifer macra by Schuchert) , also the species called 

 *^ Spirifer cf. granulosus " by Schuchert in his paper on the fauna. After 



1 Canadian Record of Sci., lî)03, Vol. IX, pp. 56-7. 



2 In a footnote it is further stated that this paper embodies results of a sur- 

 vey of St. Helen's Island which formed a part of the Honour Course in Geologry 

 and Mineralogy in the Faculty of Arts of McGill University for the session of 

 1901-1902, (of which Professor Adams had charge). 



