560 C. SCHUCHERT PALEOGEOGRAPHY OF NORTH AMERICA 



having, among- others, (Jyalkophyllum sub c a? spit o sum, Loplioplujllum, 

 Pentremites bradleyi, P. conoideus, P. godoni ?, P. subconoideus, Pro- 

 ductus longispinus, P. semireticulatus, Eumeiria verneuiliana, Spirifer 

 rockymontanus, Dielasma turgidum, Nucula shumardii, Cypricardinia in- 

 dianensis, Conocardium meekianum ?, Euomplialus spergensis, etcetera. 

 "Some seven or eight of the thirty- two or thirty-three species thus found 

 seem to be in all respects, so far as the specimens afford the means of com- 

 parison, identical with forms occurring at the celebrated Spergen Hill 

 locality" ; and the others ''belong to genera found at that locality, and so 

 closely resemble [that fauna] in their small size and other characters that 

 they may be regarded as representative forms." Meek looked upon the 

 horizon "as representing the Saint Louis limestone" (433, 434). The 

 presence of Productus Jongispinus and the corals denotes forms unknown 

 in the Spergen fauna, and it is probable that this dwarf biota represents a 

 holdover into Pottsvillian time, being presumably of the same horizon as 

 that at Old Baldy. Moreover, Ulrich has shown that this dwarf fauna 

 recurs at four different levels in the Tenneseic, and he has recently in- 

 formed the writer that a further recurrence has been discovered in the 

 Pottsvillian of Missouri. The Old Baldy locality he believes to be contem- 

 poraneous with the Arkansas Morrow formation, which he regards as of 

 early Pottsvillian time. 176 



Since the above was written, the writer was shown by Eaymond collec- 

 tions made by him in the vicinity of Old Baldy, Montana. From the 

 lower beds he has Petremites large, near P. dbesus, and P. fohesi, Produc- 

 tus cf. fasciculatus, Rhynchonella ( ?) metallica, Composita subquadrata, 

 Cleiothyridina roysii, Eumetria verneuiliana, Dielasma turgidum, etcetera. 

 Prom higher strata Syringopora multattenuata, Michelinia, Productus cf. 

 fasciculatus, P. nebrascensis, Ortliotetes robusta (small), Pugnax rocky- 

 montana, Spirifer near earner ata, and Hall and Whitfield's 8. striatus, 

 Spiriferina spinosa, Hustedia mormoni, Eumetria vera, Composita sub- 

 quadrata, Cleiothyridina orbicularis, etcetera. Near the top of the forma- 

 tion occur Productus costatus, P. semireticulatus, P. punctatus, and Com- 

 posita subtilita. These faunules, therefore, bear out the conclusion that 

 they represent the time of the Morrow of Arkansas or the earliest Potts- 

 villian. 



In regard to the Pottsville G-irty states : 



"From its faunal side it is of little interest in the way of correlation in the 

 Central and Eastern States. It will, however, probably establish some interest- 

 ing relations between beds of the West and the Southwest. The Pennsvlvanian 



178 Ulrich : Professional Paper no. 24, U. S. Geological Survey, 1904, p. 111. 



