PLATE LXXII. 
Paracyolas Ohioensis. 
Page 442. 
See Plate 95. 
Fig. 1. The right side of a specimen retaining the test. 
Hamilton group. Falls of the Ohio river. 
Paracyclas lirata. 
Page 441 
See Plate 95. 
Figs. 2-5. A series of specimens illustrating the principal varieties of form and surface markings charac¬ 
teristic of the species, as found in the Cherty beds, above the Corniferous limestone belonging 
to the Hamilton group, at the falls of the Ohio river and in Clarke Co., Ind. 
Figs. 6-19. A series illustrating the principal varieties as found in the Hamilton group in the State of New 
York. Figs. 9, 10 and 13 illustrate specimens distorted by pressure. 
Paracyclas tenuis. 
Page 443. 
See Plate 95. 
Figs. 20, 21. Two right valves enlarged to three diameters. 
Hamilton group. Bellona and shore of Cayuga lake, N. Y. 
Fig. 22. A large left valve enlarged to three diameters. 
Hamilton group. Shore of Skaneateles lake, N. Y. 
