IOWA ACADEMY OF SCIENCES. 137 



Silver Lake coal, Beede. (Trans. Kansas Acad Sci., Vol. XV. p. 30, 

 1898 ) One of the upper coal seams of the lower Waubansee (Atchison) 

 shales. It is mined in Shawnee county, Kansas, at Silver Lake, and also 

 southwest of Topeka. 



Spadra coal, Winslow. (Arkansas Geol. Sur., Ann. Kept. 1888, Vol III, 

 p. 32, 1888 ) Near middle of Arkansan series in Johnson county, Arkansas. 



Spring Creek coal seam, Broadhead. (Missouri Geol. Sur., Rept 1873-4, 

 p. 236, 1874 ) Believed to be the same as the Mystic or Mendota coal of 

 Putman county, Missouri, adjoining Sullivan county on the north. It lies 

 in the Henrietta division. 



Summit coal, McCee. (Trans. St. Louis Acad. Sci., Vol V, p. 334, 1888.) 

 In Macon county, Missouri, the highe-t seem mined. Upper part of Chero- 

 kee. 



Tebo coal, Winslow. (Missouri Geol. Sur , Vol T, p. 134, 1891.) Appel- 

 lation of the chief seam in Henry county, Missouri. Horizon is middle 

 Cherokee. 



Thayer coal, Haworth. (Kansas Univ. Quart., Vol. Ill, p. 305, 189.5 ) A 

 seam in the median part of the Thayer shales, in Neosho couny, southi ast- 

 ern Kansas. 



Topeka coal, Haworth. (Kans. Univ. Quart., Vol. Ill, p 27S, 1895.) One 

 of the seams in the Platte shales, in Shawnee county, Kansas. 



Warrensburg coal, Broadhead. (Missouri Geol. Sur., Iron Ores and Coal 

 Fields, pt. ii, p. 184, 1873 ) A thin seam in the upper part of the Cherokee 

 division, in Johnson county, Missouri 



Wapello horizon, Bain. (Iowa Geol Sur, Vol. IX, p. 99, 1899.) An 

 extensive coal in southeast Iowa, lying in the lower part of the Cherokee. 



Waverly coal, Winslow. (Missouri Geol. Sur., Vol. IX, Sheet Rept. No. 

 1, p. 60. 1892 ) In eastern Lafayette county, Missouri, the lowest seam 

 mined. Cherokee division. 



Wbee'er coal, St. John. (Iowa Geol. Sur., Vol. I, p. 276, 1870 ) One of 

 the lower coals of the Marais des Cygnes, in Warren county. Iowa. 



What Cheer coal field. Bain. (Iowa Geol. Sur , Vol. IV. p. 284, I89.i. 

 This coal seam, in Keokuk and Mahaska counties, Iowa, lies very near the 

 base of the Cherokee. 



Wier City Pittsburg View, Haworth and Kirk. (Kansas Union Qua t , 

 Vol. II, p 105, 1894.) In southeast Kansas, the most important seam of the 

 Cherokee. 



VOLCANIC NECKS OF PIATIGORSK, SOUTHERN 

 RUSSIA. 



BY CHARLES E. KEYES. 



(Abstract.) 

 On the Rostov and Wladikavkas railroad, in southern 

 Russia, there rises out of the flat steppes, a few hours be- 

 fore reaching the last mentioned place, a remarkable group 



