Silurian Fossils. 11 



Clathropora frondosa, Hall. 

 A wretchedly preserved specimen showing" the fenestrules 

 occurs in the West Union bed at the spring on Big Salt Lick 

 creek, one mile south of Glen Springs, in Lewis county, Ky. 



RhYNCHOTRETA AMERICANA, Holl. 



Similar to Rhynchotreta aniericana from the Waldron clay 

 of Indiana, but in some specimens the beak is less prolonged, 

 although equally acute. In some specimens the two middle 

 plications on the median fold are conspicuously more ele- 

 vated than the other two, but in others all four plications on 

 the fold reach about the same elevation. Sinus of the pedicel 

 valve with three plications. Lateral plications usually three, 

 but sometimes two or four. 



West Union bed, in the quarry at the southeastern corner 

 of West L^nion, Ohio. Also at the spring on Big Salt Lick 

 creek one mile south of Glen Springs, and one mile south of 

 Carrs station, in Lewis county. At the locality south of Carrs, 

 an aberrant specimen was found with two plications on the 

 fold, one in the sinus, and two lateral plications on each side 

 of the fold and sinus. 



Camarotoechia congruens, sp. nov. 

 Plate II, Figs. 3. A. B. 



Shell small, 6 mm. long, 6.5 mm. wide, both valves mode- 

 rately and rather evenly convex. Four plications occupy the 

 median fold of the brachial valve, and about eight lateral pli- 

 cations are found on each side. The most characteristic fea- 

 ture is the very low elevation of the median fold, m some 

 cases almost imperceptible, combined with the slight differ ■ 

 ence in size of the plications occupying the median fold and 

 those immediately adjacent. While usually the plications on 

 the fold are slightly larger, in some cases the difference is 

 almost imperceptible. 



In the upper part of the Alger clay division of the Crab 

 Orchard formation, between \^alley and the W. H. Lawrence 

 store, in Lewis county. Kentucky. 



11 



