[vviLMAMs] FOSSIL FAUNAS OF THE ST. HELEN'S BRECtJlAS 207 



15 Choiiostrophia montrealeiisi^ iiov. ?p. 



16. Chonostrophia jerveiisis n. sp. 



Middle Devonic Fauna. 



17. Dalinanolla plainconvexa. Hall? 



18. Spirifer macra. Hall. 



19. Spirifer ef. graniilopii?, (Conrad). 



A? Schuclicrt's paper is the latest r-tatement of the case in print, I 

 ^vill quote at length his conclusions: "The foregoing evidence shows 

 clearly that ttvo distinct faunas are represented in St. Helen's Island,— 

 one the TJrlderherginn. older Ihan Ihe agglomerate, and another, from a 

 hlocJc in the agglomerate, of Middle Devonic age." " The Ilelderbergian 

 fauna is apparently related wilh that of New York, and belongs to the 

 fades occurring on the western side of the Appalachian folds, fhe writer 

 has collected this fauna at Dalhousie, New Brunswick, and from the 

 Gaspé region, Quebec, and both are of another fades and belong to an- 

 other basin." "The presence of Rhipidomella, recalling R. musculosa; 

 Spirifer concinnus; an early variety of S. mnrchisoni; Spirifer n. 'sp., 

 Spirifer n. sp., connecting phylogeneiically S. concinnus and S. arenosus; 

 Camarotoechia pleiopleura; Gypidula pseudogaleata, and R. œquiradiata, 

 are characteristic Becraft zonal species. However, the Ori^lcaman re- 

 minders, like R. near musculosa, S. murchisoni, S. near arenosus, prove 

 that Ihe Saint Helens Island Helderbergian is pretty well up towards 

 the top of the New York section, and may represent both the Becraft and 

 Tvinqstoii tones.-. " >>//-/frr macra and S. granulosus establish the fact 

 that, in the region of Montreal, there was once a formation of marine 

 origin later ihan the Helderbergian and as recent as the Onondaga^ 

 (Corniferovs) ; further, that the agglomerate of St. Helen's Island and 

 other places about Montreal is not older than later Middle Devonic time. 

 Its age is probably more recent, and there may be further palœoniologt- 

 cal evidence in the agglomerate." 



In commenting upon these conclusions the first point,— that 

 there are two distinct faunas represented, is confirmed by the later evi- 

 dence to be discussed beyond. The second point— that the age of the 

 fauna is Helderbergian is also confirmed. But the third point— that 

 there is a " Middle Devonic fauna " in these breccias, appears to be un- 

 supported by the evidence now in hand. 



1 ]. c, pp. 252-253. 



