The New Species of Brachiopoda. 36T 



Shell somewhat similar in general expression to that of Con- 

 chidmm Knightly Sow., but smaller, more sparsely and closely 

 plicated. 



Corniferous limestone. Near Louisville^ Kentucky, 



Conchidium Greenii. 



Plate 11, figs. 5-7. 

 Conchidium Greenii, Hall. Palaeontology of N. Y. , vol. VIII, pt. 2, p. 368, pi. 

 Ixvi, figs. 20-23. 1894. 



Shell subequally biconvex, ventricose, subcircular in marginal 

 outline. Umbones full and rounded, both incurved, that of the 

 pedicle- valve somewhat elevated. There is no evidence of median 

 fold and sinus. Surface of each valve bearing, over the pallial 

 region, from forty-five to fifty rounded plications, which very 

 gradually increase by implantation and become more numerous 

 anteriorly. . These plications are of slightly unequal size, which 

 appears to be due to variation in the rate of their multiplication. 

 In the umbonal regions the plications are obsolete. 



Niagara dolomites. JVear Milwaukee, Wisconsin. 



Conchidium crassiplica. 



Plate 11, figs. 3, 4. 



Conchidium crassiplica, Hall. Palaeontology of N. Y,, vol. VIII, pt. 2, p. 

 369, pi. Ixvi, figs. 24, 25. 1894. 



Shell elongate, subelliptical in outline. Yalves subequally con- 

 vex, depressed above ; cardinal slopes broad and abrupt on both. 

 Umbo of the pedicle- valve erect, not prominent, surface slightly 

 elevated medially. Umbo of brachial valve depressed, apex con- 

 cealed ; median region depressed anteriorly ; surface of both 

 valves bearing broad rounded plications, separated by deep 

 grooves. Of these plications there are from eight to ten on each 

 valve over the pallial region; by dichotomizing these become 

 more numerous anteriorly. 



Niagara group. JVear Louisville, Kentucky. 



Conchidium Georgiae. 



Plate 11, figs. 10, 11. 

 Conchidium Georgice, Hall. Palaeontology of N. Y., vol. VIII, pt. 2, p. 369, 

 pi. Ixvi, figs. 18, 19. 1894. 



Pedicle-valve unknown ; brachial valve trilobed by the develop- 

 ment of a strong-median fold which extends from apex to mar- 



