TJic Fauna of ihc Ma.vz'illc Limestone. 383 



This species is characterized by its punctate structure, thick 

 shell, and obliquely truncated beak. 



Horizon and loeality. — Maxville limestone. 

 Upper zone: Gladstone Mills. Thom})son Residence. Below 



Thompson Residence. White Cottage. 

 Shale-nodular zone : Cut No. 5, Mouth of Hough Hollow, Mt. 



Perry-Fultonham ; Kroft Bridge. White Cottage ; Stimmel 



Residence. Maxville ; Smith Chapel. Logan. 

 Lower zone: Cut Xo. 2. Cut No. 3. Cut No. 4?, Cut No. 5, Mt. 



Perry-Fultonham. 

 Undetermined zone: Middle of Cut No. 6, Mt. Perry-Fulton- 

 ham. 



SEMTNULA SUBQUADRATA-Hall. 



1858. Afhyris siibqiiadrafa. Hall, Geol. Surv. Iowa, Vol. I, pt. II, p. 70"^ 

 pi. -27, figs. 2 a-d ; p. 708, fig. 118. 

 Kaskaskia limestone : Chester, Illinois ; Crittenden County, Ken- 

 tuck\'. 

 1877. Athyris subquadrata ? Hall and Whitfield, U. S. Geol Expl. 40 

 Par., Vol. IV, p. 271, pi. 5, figs. W, 20. . 

 Wasatch limestone: Utah. 

 188(i. Afhyris subquadrata. Heilprin, 2d Geol. Surv. Penn., Ann. Rep. 

 for I880, p. 453, p. 440, fig. 2. 

 Mill Creek limestone, Upper Coal Measures : Wilkesbarre, Penn- 

 sylvania. 

 188(5. Atliyris subquadrata. Heilprin, Proc. and Coll. Wyo. Hist, and 

 Geol. Soc., Vol II, pt. II, p. 2(W, fig. 2. 

 Mill Creek limestone, Upper Coal Measures : Wilkesbarre, Penn- 

 sylvania. 

 1891. Athyris subquadrata. Whitfield, .Ann. N. Y. Acad. Sci., Vol. V, 

 p. 585, pi. 14, figs. 1-8. 

 Maxville limestone: Newtonville and Maxville, Ohio. 

 1894. Scuiiuula subquadrata. Hall and Clarke, Int. to Study of Rrach., 

 pt. II, pi. :35, figs. 13, 15. 

 Chester limestone: Crittenden County, Kentucky. 

 St. Louis limestone: Pella, Iowa. 

 18!'4. Alhyris subquadrata. Keyes, Mo. Geol. Surv., Vol. V, p. 92. 

 Kaskaskia limestone: Ste. Mary, Missouri. 

 3 



