REPORT OF THE DIRECTOR I914 I27 



sion — the Utica shale of the Ordovicic, the Marcellus of the Middle 

 Devonic, and these Genesee-Portage shales of the Upper Devonic 

 • — there is throughout a common character in the aspect of the 

 contained marine fauna. Deficiency of lime makes all species thin 

 shelled; all species are of rather depauperated size, phosphatic 

 brachiopods {Lingula, Orbiculoidea etc.) abound while the lime- 

 shelled species are few, small cephalopods are frequent while other 

 MoUusca are rarer and fragile. The statement is only a natural 

 expression of the effect of like conditions on various faunas. 



1 The faunas of the Genesee-Portage are strictly marine; 



2 They are, taken as a whole, of the deep water type whiJi em- 

 phasizes the Portage fauna in its highest development (Intumescens 

 fauna) ; indeed, they represent this fauna; 



3 The shales carry a thin lime deposit, continuous over a great 

 extent of latitude and essentially a mass of pteropods. I have in- 

 dicated that this Styliolina or Genundewa limestone holds the ptero- 

 pod Styliolina in numbers of 50,000 — 100,000 to the cubic inch. 

 By analogy these minute creatures are pelagic open sea animals. 

 These limestones, too, carry the Intumescens fauna in a typical 

 though prenuncial development ; 



4 The shales abound in exudations of FeSo ; indeed, the base of 

 the Genesee shale in western New York rests on a continuous layer 

 of pyrite extending for 100 miles and carrying the relicts of a fauna 

 (Hamilton) dismally dwarfed by the foul conditions which it hope- 

 lessly tried to survive. 



These features of the fauna and their physical surroundings I 

 have found illuminated by the parallel conditions prevailing in the 

 depths of great inclosed seas like the Mediterranean and the Black 

 Sea, where limeless waters, free liberation of sulphur in connection 

 with a rapid organic decomposition under great pressure, are pro- 

 ducing such foul bottoms with sulphide compounds, dwarfed and 

 thin-shelled Mollusca, always, of course, with the accretion of what 

 may fall in from flotage and dying pelagic life. These inferences 

 as to the deep water origin of the black shales are corroborated by 

 their greater thickness westward of New York. 



In extraordinary contrast to these conclusions is the proposition 

 put forward by Professor Grabau that the bituminous shales are 

 delta deposits, brought in by a putative southwestern river flowing 

 northeasterly, discharging this singular supposed fluviatile-con- 

 tinental mass over an area of many hundreds of square miles. This 

 view seems to the writer the extreme expression of a recent obvious 

 tendency to magnify the part contributed by alluvial floors and fans, 

 desert desiccation and other continental factors to the upbuilding of 

 the geological column. 



