374 NEW y ORK STATE MUSEUM 



and, while the whole mass attains a thickness of only about ioo feet, there 

 are many alternations of black with the gray shale. At Lexington and 

 other localities of the black shale the fossils are those usual in similar 

 deposits eastward, Sty Molina fissurella, Orbiculoidea loden- 

 sis, Ling u la spat u lata, Schizobolus con centric us etc. ; but 

 at Delphi Kindle has found, pyritized in blue shale, Goniatites w abas li- 

 en sis and G. delphiensis Kindle, both species of Gephyroceras or 

 small individuals of Probeloceras or Manticoceras in a gephyroceran stage. 

 Spathiocaris occurs in these shales, as it does throughout the black and 

 gray bands of the Genesee and Portage in New York. No element of the 

 fauna obtained from these Indiana beds, however, argues very strongly for 

 equivalence with New York faunas later than Genesee. 



The development of this shale at Irvine Ky. is stated by Williams to 

 continue upward beyond the Devono-Carbonic boundary,' while the beds at 

 Big Stone Gap he finds to be underlain by limestone carrying Onondaga 

 corals. Girty calls attention further to Shaler's opinion that the formation 

 in Kentucky and Tennessee represents the entire series of formations from 

 the top of the Oriskany to the Chemung. The earliest incursion of these 

 black muds on the New York area is represented by the Marcellus shales 

 when the sediments were distributed northward and eastward from the deep 

 waters lying off the southern coast of the Appalachian gulf, while the faunas 

 of the limestones embedded in these black Marcellus shales were derived 

 from the west. 



The small group of species described by Dr Girty is from the base of 

 the black shale and shows some characters which are common to both Mar- 

 cellus and Genesee shales in New York ; 2 but one Lingula, L i n g u 1 i p o r a 



1 Am. Jour. Sci. 1897. 3:398. 



2 The fauna reported consists of the following: 



(1) Lingulipora williamsana, (2) Liorhynchus quadricostatum, 

 (3) Prioniodus armatus, (4) Sporangites huronensis?, (5) Orbiculoidea, 

 (6) Meristella cf. h a s k i n s i, (7) Plethospira s o c i a 1 i s. Of these 2, 3, 4 are 

 known alike in both Marcellus and Genesee ; 7 is very similar indeed to P. r u g u 1 a t a, 



