GLEN DEAN CONODONTS 



27 



specimens there is no main denticle or cusp 

 above the pit, only small denticles. I would 

 interpret the form as consisting of a bar 

 with or without a small main cusp, a deep 

 pit near the anterior end of bar, and, 

 rising from the anterior end of the bar, an 

 antero-lateral process directed downward 

 and slightly backward, bowed convexly 

 posteriorly, and bearing several stout dis- 

 crete denticles, the antero-lateral process 

 considerably larger than main bar. The 

 specimens seem more closely related to 



Ligonodina than to any other described 

 genus. 



Material studied. — 140 specimens. 



Distribution. — Renault, Paint Creek, 

 Golconda, Glen Dean, Menard, Clore and 

 Kinkaid Formations of Illinois, Indiana, 

 and Kentucky, the Pella Beds of Iowa, and 

 the Delaware Creek Member of the Caney 

 Shale of Oklahoma. 



Repository. — Illinois State Geological 

 Survey, 3P87, 3P88 (figured specimens). 



REFERENCES 



BiscHOFF^ GuNTHER, 1957, Die Conodonten-Strati- 

 graphie des rheno-herzynischen Unterkarbons: 

 Hess. Landesamt. Bodenf., Abhl., Hf. 19, p. 

 1-64, pi. 1-6. 



Branson, E. B., and Mehl, M. G., 1940, Caney Con- 

 odonts of Upper Mississippian age: Denison 

 Univ. Bull., Jour. Sci. Labs., v. XXXV, p. 167- 

 178, pi. V. 



Branson, E. B., and Mehl, M. G., 1941, New and 

 little known Carboniferous conodont genera: 

 Jour. Paleontology, v. 15, no. 2, p. 97-106, pi. 

 19. 



BuRMEiSTER, H. C. C, 1847, Handbuch der Ento- 

 mologie, v. 5, p. 364. 



Cooper, Chalmer L., 1947, Upper Kinkaid (Missis- 

 sippian) microfauna from Johnson County, Illi- 

 nois: Jour. Paleontology, v. 21, no. 2, p. 81-94, 

 pis. 19-2.?; reprinted as Illinois Geol. Survey 

 Rept. Inv. 122. 



Elias, Maxim K., 1956, Upper Mississippian and 

 Lower Pennsylvanian formations of south-cen- 

 tral Oklahoma: Petroleum geology of southern 

 Oklahoma: Am. Assoc. Petrol. Geol., v. 1, p. 

 56-134, pi. I- VI. 



Flugel, von, Helmut, and Ziegler, Willi, 1957, 

 Die Gliederung des Oberdevons und Unter- 

 karbons am Steinberg westlich von Graz mit 

 conodonten: Naturwissenschaft. vereines f. 

 Steiermark, Mitteil. Bd. 87, p. 25-60, pi. 1-5. 



Hass, Wilbert H., 1950, Age of lower part of Stan- 

 ley Shale: Am. Assoc. Petrol. Geol. Bull., v. 34, 



no. 7, p. 1578-1584. 



Hass, Wilbert H., 1953, Conodonts of the Barnett 

 Formation of Texas: U. S. Geol. Survey Prof. 

 Paper 243-F, p. 69-94; pi. 14-16. 



Hass, Wilbert H., 1954, Age of some black shales 

 in cores from northeast Mississippi: Mississippi 

 Geol. Soc. Guide Book, 11th Field Trip, p. 

 32-33. 



Rexroad, Carl B., 1957, Conodonts from the Ches- 

 ter Series in the type area of southwestern lUi 

 nois: Illinois Geol. Survey Rept. Inv. 199, p. 

 1-43, pi. 1-4. 



YouNGQUiST, Walter, and Miller, A. K., 1949, Con- 

 odonts from the late Mississippian Pella Beds 

 of south central Iowa: Jour. Paleontology, v. 23, 

 no. 6, p. 617-622, pi. 101. 



Illinois State Geological Survey Report of Investigations 209 

 27 p., 6 pis., 14 figs., 1 table, June 1958. 



