LOWER CARBONIFEROUS FOSSILS. 525 



Formation and locality: Madison limestone, Crowfoot Ridge, Gallatin 

 Range, bed 31; J. P. Iddings and W. H. Weed Keokuk age, Keokuk, 

 Iowa; Warsaw and Nauvoo, Illinois; New Providence, Indiana; Clark 

 County, Missouri; Nevada. 



LEPT.ENA Dalman, 1828. 



Lept^ena rhomboidaus Wilckens. 



Conchita rJiomboidalis Wilckens, 1709: Nachricht von selten Versteinerungen, p. 77, 



PI. VIII, figs. 43, 44. 

 Leptcena tenuistriata Hall, 1847: Pal. New York, Vol. I, p. 108, PI. 3lA, figs. 4r/-4</. 

 Stroplwmena rJiomboidalis White, 1875: Wheeler's Expl. Surv. W. 100th Merid., Vol. 



IV, p. 85, PI. V, fig. 5. Hall and Whitfield, 1877 : King's U. S. Geol. Expl. 40th 



Par., Vol. IV, p. 253, PL IV, fig. 4. Walcott, 1884: Mon. IT. S. Geol. Survey, 



Vol. VIII, p. 118. 

 Leptwna rliomboidalis Hall and Clarke, 1892: Pal. New York, Vol. VIII, Pt. I, 



p. 279, PL VIII, figs. 17-31; PL 15a, figs. 40-42; PL 20, figs. 21-24. 



The amazing stratigraphic and geographic range of this species makes 

 it too well known to require any additional description. It is a compara- 

 tively rare form in the Yellowstone National Park, and is found only in the 

 lower part of the Madison limestone. 



Formation and locality: Madison limestone, Crowfoot Ridge, Gallatin 

 Range, top of bed 25; J. P. Iddings and G. M. Wright. West of Antler 

 Peak, Gallatin Range; A. C. Gill. Crowfoot Ridge, Gallatin Range, top of 

 bed 24; J. P. Iddings. East side of Lamar Valley, mouth of Soda Butte 

 Creek, Absaroka Range; Arnold Hague. Universally distributed, from the 

 Trenton to the Waverly. 



CHONETES Fischer de Waldheim, 1837. 



Chonetes loganensis Hall and Whitfield. 



PL LXVIII, figs. 5a, 5b, 5c. 



Chonetes lor/anensis Hall and Whitfield, 1877: King's U. S. Geol. Expl. 40th Par., Vol. 

 IV, p. 252, PL IV, fig. 9. 



This form is very abundant in the Carboniferous limestones of the Yel- 

 lowstone National Park. Specimens have been examined from a number 

 of localities, and they can be referred without hesitation to C.lofjancnsis Hall 



