428 A. W. GRABAU THE SHEEBUEXE SAXDSTOyE 



Two hundred and sixty feet higher are sandstones with Spirifer mesastri- 

 alis. S. mucronatus, Tropi-d-oleptiMS carinatus, etcetera, representing the 

 Ithaca formation/^ 



In the section on AVliitney Brook, north of Maryland, the following 

 members are pertinent. 



Twenty-five feet above the beds regarded by Prosser as forming the top 

 of the Hamihon are bluish argillaceous and even arenaceous shales with 

 few marine fossils, but with plenty of "fncoidar^ and mud markings. 

 These are regarded as of the horizon of the Sherburne and they contain 

 fragments of 



spirifer /nucroudtu.i- and 

 Lioptrria dcJcaui — both rare. 



Ten feet higher the following fauna was obtained by Prosser : 



1. Lingida punciaia Hall ? (c) 



2. Tropidoleptus carinatus ( Con. i rr 



3. Spirifer sp. rr 



4. Xuculites triqueter Con. rr 



5. Bfllfroplion ef. Uda Hall rr 



and plant stems referred doubtfully to 



6. ( '; \ RJiodia pinnaia Dawson rr 



Thirty-five feet higher, or TO feet above the top of the Hamilton, are 

 bluish, slightly irregular shales, which inclose a 6-inch fossiliferous layer 



which has furnished^- 



1. Spirifer mucronatus (Con.) (r) 



2. Sp. mesistrialis Hall ? (rr) 



3. Sp. frimtjriatus (Con.) (rr) 



4. Chonetes set ig era Hall (rr) 



5. Chonetes tepid us Hall (rr) 



6. Leptostrophia cf. prrplana (Con.) ^r) 



7. LinguJa sp. (;it) 

 S. Goniophora harniltonensis Hall (rr) 

 9. PaJ<roneiIrj constricta (Con.) (rr) 



One hundred and thirty feet higher, or 200 feet above the top of the 

 Hamilton, an irregular concretionary sandstone and bluish and olive 

 shales carry the following fauna^^ 



1. Cyrtina harniltonensis Hall (c) 



2. Spirifer mucronatus (Con.) (rr) 



3. Tropidolfptus r-arinatus (Con.) (r) 



4. Liorhynchus sp. (r) 



"^ Prosser : Loc. cit.. p. 212. 

 ^Prosser: Loc. cit.. p. 217. 

 "^3 Prosser : Loc. cit.. p. 217. 



