Silurian Fossils. 30 



Fig. 10 — Chonetes colliculus, sp. nov. A, pedicel valve. B, an- 

 terior view, outline, intended to show the convexity. C, vertical sec- 

 tion. From the upper part of the old George W. Defenbaugh quarry, 

 southeast of Kokomo, Indiana. Magnified 3 diameters. 



Fig. 11 — Rhipidomella magnicardinalis, sp. nov. A, interior view 

 of posterior half of brachial valve. B, vertical section, showing the 

 great length of the cardinal process. C, cast of the pedicel valve. 

 Drawings A and B are very imperfect, and serve only to show the 

 great length of the cardinal process. At the Spring on Big Salt Lick 

 creek, one mile south of Glen Springs, Lewis county, Kentucky. West 

 Union bed. Magnified 2 diameters. 



Fig. 12 — Amplexus septatiis, sp. nov. A, natural vertical section. 

 B, cross-section, magnified 3 diameters, showing primary and second- 

 ary septa. At the top of the old George W. Defenbaugh quarry, south- 

 east of Kokomo, Indiana. 



Fig. 13 — Strophcodonta (Brachyp) ion) planus, sp. nov. A, pedi- 

 cel valve, cast, showing the dental ridges and the median septal ridge. 

 B, convexity of this valve. C, part of a ventral valve, apparently 

 worn, with only the posterior part of the median ridge preserved. 

 West Union bed, at West Union, Ohio. 



Fig. 14 — Spirifcr rcpertus, sp. nov. Brachial valve. West Union 

 bed at Harin Hill, four miles west of Valley, in Lewis county. Ken- 

 tucky. Magnified 2 diameters. 



Fig. 15 — Phtystrophia pauciplicata, sp. nov. Brachial valve, cast 

 of interior; the impression of the cardinal process along the middle 

 part of the cast of the cavity between the crural plates is not shown. 

 West Union bed. at the quarry in the southeastern corner of W^est 

 Union, Ohio. Magnified 2 diameters. 



Fig. 16 — Chonetes vetustiis. Foerste. Pedicel valve. Only 53 

 radiating striations are indicated in the drawing. In full-sized speci- 

 mens the number varies from sixty to seventy. The length of the 

 hinge spines nearest the beak is not known accurately. Near the top 

 of the Alger clay division of the Crab Orchard formation, a mile west 

 of Valley, in Lewis county, Kentucky. Magnified 3 diameters. 



Fig. 17 — Favosites pyrifonne-kokomocnsis, var. nov. A, section 

 of a corallite showing the tabulae and septal spines. B. C, section show- 

 ing three pores and the location of numerous septal spines. D, coral- 

 lite, showing location of pores on the walls. Near the top of the old 

 George W. Defenbaugh quarry, southeast of Kokomo, Indiana. Mag- 

 nified 5 diameters. 



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