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NEW YORK STATE MUSEUM 



careous sand cliffs carrying the extraordinary profusion of Ostra- 

 coderm and Crossopterygian fishes and beautifully preserved ferns. 

 The plants are natural land wash while the fishes are presumably 

 the natives of the stream mouths, probably migrant into the fresh 

 waters for spawning purposes, hke the salmon which today maintain 

 this historic procedure in the streams which traverse these rocks. 

 Beneath these remarkable cliffs is a ' gray boulder shale whose 

 boulders are more largely of the fossihferous limestones and less 

 of the crystallines than in the Bonaventure. We are not yet pre- 

 pared to be positive regarding the origin of this underlying boulder 

 shale. Its matrix resolves easily to clay and squeezes out over the 

 landwash, setting its boulders free. Its component blocks are frac- 

 tured, impressed and ice-scratched. The students of the fish-bearing 

 Magouasha beds above are quite in accord in regarding them as of 

 Upper Devonic age, though this conclusion has not as yet full con- 

 firmation from the other biotic elements. 



The late Doctor Ells found evidence satisfactory to him of an 

 unconformity within the mass of the Bonaventure conglomerate 

 which was assumed to divide the time of its deposition by a slight 

 diastrophy. If this interesting division can be fully demonstrated, 

 it establishes a very noteworthy agreement with the Old Red of 

 northern Scotland which is marked by a widespread disconformity 



of this kind. 



Origin of the Intumescens-fauna. It was essentially with the 

 help of Professor Kayser's studies of the " Intumescens fauna " of 

 the Upper Devonic, that the writer prosecuted his investigations of 

 this fauna in America. The " Intumescens-fauna " of the Genesee- 

 Portage stage has proved to have had a profuse and highly char- 

 acteristic development in western New York, though quite suddenly 

 losing itself thence in all directions. Eastward its place is taken 

 in contemporaneous strata by the brachiopod faunas of the Ithaca 

 and Chemung groups, so that no evidence of its existence is to be 

 found on the western shores of old Appalachia. Westward traces 

 of it are found here and there, in Iowa, in Manitoba, a striking 

 development in Montana. The fauna, it was claimed by the writer, 

 took its origin from the region of its great development m northern 

 Siberia (Timan), and its dispersal was eastward along American 

 strands into the interior sea of early Upper Devonic Appalachia 

 where, favored by its isolation, it burst out into a fulness of de- 

 velopment. Professor Schuchert, in the construction of his paleo- 

 geographic maps, has felt it necessary to introduce this fauna from 



