[WILLIAMS] FOSSIL FAUNAS OF THE ST. HELEN'S BRECCIAS 213 



appears to contain part of the Spirifer arenosus fauna of St. Helen's 

 Island, is here inserted, viz. :) 



1. Chonetes (Eodevonaria) Imdsonicus metatype gaspensis, Clarke. 



2. Spirifer pennatus, var. Helense, var. nov., H. S. W. 



3. Tentaculites Schlotheinii Koken, (cf. T. elongatus, Hall). 



4. Cf. Avicula textilis, Hall. 



Discussion of the Faunas and tiikir stratigraphic significance 



A review of these faunas confirms the estimate originally placed 

 upon their stratigraphic correlation : Lots 2 and 3 are evidently equi- 

 valent to some portion of the Lower lleldorberg of New York and in 

 particular are closely related to the fauna of the upper Pemtameruls 

 (Becrafts) limestone. Of the total lists of specimens from Lots 2 and 3, 

 twenty-six names are listed by Schuchert ^ as belonging to the Helder- 

 bergian fauna, all but one (Orthis (Damanella) concinna, Hall) occur 

 in the Xew York area. Of these twenty-li\e species 



6 are listed C. (Cœmans limestone). 



14 are listed B. (Becraft limestone). 



18 are listed S. (New Scotland beds. 



Tlie cliaracter of the rock may account for the greater number of 

 New Scotland species, while the presence of Gypidula pseudogaleata, and 

 Camarotœchia ventricosa indicate a later type of the fauna which did 

 not appear in the New York area till the Becraft horizon. 



inspection of tlie lists, therefore leaves little doubt as to the equi- 

 valency of the fauna in geaieral with the typical Helderbergian of New 

 York. This is also in harmony with the conclusion reached by Schu- 

 chert from his study of the material in the McGill College Collection. 



The Spirifer arenosus fauna (253.1) shows by its list of species 

 intimate relationship with the typical Oriskany fauna of New York 

 state. The following species viz., 



Eatonia peculiaris, 



Eatonia cf. Whitfield i, 



Spirifer arenosus, 



Spirifer gaspensis, 



Cyrtina rostrata. 



Metaplasia pyxidata, 

 associated together signify a fauna wliicli has not been greatly modified 

 from the tyi3ical Oriskany, and the combination signifies also a stage 

 later tlian the typical Helderbergian fauna. 



1 Scimchevt, C, Lower Devonic aspect of the Lower Helderberg and Oriskany 

 formation, Bull. Geol. Soc, Vol. II. 1900, p. 278. etc. 



