PLATE XXXVII. 



. PAGE. 



Fig. 1. Cypricardites caswelli Foerste 561 



1 a, Lateral ; 6, front ; c, hinge view. Same specimen as figs. 12 a-b. plate 25. S. H. 0. 

 Collection of Geo. Caswell 

 Fig. 2. Nuculites ( Cleidophorus ) ferrugineum Foerste t 564 



2. b, Cast, natural size; a, magnified. T. F. O. Ohio State University collection. 



Fig. 3. Craniella clintonensis Foerste 565 



3. a, Interior cast, the details are scarcely visible ir. the original specimen ; *. an 



elevation of the same. T. F. O. Collection of Dr. Chas. Welch. 



Fig. 4. Tellinomya ^equilatera Hall 562 



4. a, Cast of one valve magnified ; b, curvature across the shell ; c, curvature length- 



wise with the shell, natural size. T. F. O. Collections of Dr. Chas. Welch ; 

 d, lateral; e, front; f, hinge view of Tellinomya equilaiera, Hall, from the 

 Coralline limestone of Schoharie, N. Y., copied from Pal. N. Y. Vol. II, Plate 75, 

 Fig. \b,d,i.. 



Fig. 5. Avicula whiTFIELDI Foerste 558 



^ 5. Cast of exterior. Same as Cypricardites ferrugineum of Hall and Whitfield, 

 Pal. Ohio, Vol. II, Plate V, Fig. 11. Prepared from the ■ original cast. The 

 details near the posterior end of the hinge line are not well shown in the origi- 

 nal, and at this point it would have been better if the drawing had been left 

 more non-committal. Possibly the posterior margin was not incurved here but 

 continued its convexity as far as the hinge line. T. F. O. Ohio State University 

 collection. 



Fig. 6. AVICULA. 



6. Cast of interior with a little of the exterior preserved near the hinge. S, H. O. 



Collection of Geo. Caswell. 



Fig. 7. Modiolopsis subrhomboidea Simpson 560 



7. u, Interior cast showing concentric strialions and interior muscular impressions. 



H. O. ; b, interior cast type ; copied from Rep. Penn. Geol. Survey, Diction- 

 ary of fossils of Pennsylvania, p. 411, Vol. I, Fig. Vn., from Clinton shale, 

 above fossiliferous ore, McKee's ore bank, northeast of McKee's house, 

 Ferguson Valley, 7 miles northwest of Lewistou, Mifflin county, Pennsylvania. 



Modiolopsis rhomboidea Hall 560 



a, Interior cast, showing a strong anterior muscular scar. H. O. b t cast of interior, 

 type, copied from Dictionary of Fossils of Pennsylvania, p. — , Fig. — , from the 

 Upper Silurian at Arisaig, Nova Scotia. 



Cypricardinia undulostriata Hall 561 



a, Right valve. HO; 4, leftvalve. S. H.O.; c, right valve, type, copied Ironi Pal. 

 N. Y. Vol. II, Plate 59, Fig. 6a from Niagara shale at Lockport, N. Y. 



Tellinomya elliptica Hall 562 



Copied from' Pal. N Y. Vol. II, Plate 30, Fig. 44 ; from upper Clinton sandstone, 

 south of Mohawk Herkimer Co., N. Y. 



MyTilarca mytiliformis Foerste 559 



u, Left valve ; b, elevation along the anterior margin ; c, elevation across the valve. 

 T. F. O. Collection of Prof. E. W. Claypole. 



Tbuinomya (Nucula?) sociaws Foerste 563 



a. Anterior; b, left valve ; c, posterior view. H. O. Beavertown, Marl. 



TeW/INOmya (Nucula?) minina Foerste 563 



a, Anterior ; *, left valve ; c, hinge views, same as figs. Sa-b-c, of plate 25, type. 

 H. O. Beavertown Marl. 



Elpe ulrichi, Foerste 532 



a, Left valve ; b, anterior ; c, hinge view. H. O. " Orthoceras block." 



Tellinomya (Nucula?) clintonensis Foerste 563 



Right valve. Collection of Prof. E- W. Claypole. 



