EARLY DEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA 29 



cated on those lists. We shall, therefore, make our way with the best light 

 at our command.' 



Locran retrarded this entire series of beds as " Upper Silurian lime- 

 stones" [/of. cit. p. 393] or more definitely "a great development of strata 

 of the age of the Lower Helderberg group" [p. 391]. The closer scrutiny 

 of the fossil contents led Billings to conclude that " the two lower divisions 

 [i and 2] are most probably Silurian ; about the age of the Helderberg of 

 the New York geologists. The upper two members [7 and 8] are nearly 

 of the age of the Oriskany sandstone, and are therefore about the base of 

 the Devonian. Divisions 4, 5 and 6 may be regarded as constituting 

 passage beds between the Upper Silurian and Devonian."'' 



Ells (1883) states that " of these Gaspe limestones it is now consid- 

 ered that only the two lower members, representing a thickness of 160 feet, 

 can with propriety be assigned to this [Siluric] system while the preponder- 

 ance of fossils of Devonian aspect even in the basal bed renders it probable 

 that the whole may ultimately be transferred to the Devonian system." ^ 



This farsio;hted view has foreshadowed that at which we have arrived 

 with the aid of detailed and conclusive evidence. 



On a previous occasion we have briefly discussed the relation of the 

 fauna as a whole to the series in New York,* and at that time made the 

 following propositions : 



Logan's subdivision of the limestone series was given with lucidity 

 and exactitude but seems hardly to clothe this unique succession with the 

 dignity and importance it merits. Dr Ami has suggested that the upper 

 beds 7 and 8, be termed the Grande Greve limestones from the little village 

 on the peninsula where these strata are best exposed and most readily 

 accessible. . . . This name seems happily chosen and we have 

 thought that with equal propriety the lower beds i and 2, exposed in the 



' Dr Whiteaves has made it possible for us to institute comparisons with Billings's 

 original specimens whenever doubt has arisen concerning the identity of our own material, 

 and to refigure in many cases these types. 



*Paleoz. Foss. 1874. v. 2, pt i, p. 2. 



3Rep't Geol. Gaspe Penin., Geol. Sur. Can. Rep't Prog. 1880-82. 1883. p. 15 DD. 



+ N. Y. State Mus. Mem. 3. 1900, p. 81. 



