186 SYNOPSIS OF AMERICAN FOSSIL BRACHIOPODA. Lb^llST. 



Conchidium decussatum (Wbiteaves). Silurian. 



J'eutamerus decusaatiis Wbiteaves, Canadian Record of Science, 1891, p. 29;"), pi. 



3, figs. 3, 4.— Calvin, Bnll. Lab. Nat. Hist. State Univ. Iowa, XT, 1892, p. 



164, pi. 11, iigs. 1-3; pi. 12, lig. 2. 

 Conchidium decussatum Hall and Clarke, Pal. N»'\v York, \"III, I't. II, 189.'>, p. 



235, pi. 65, Iigs. 1, 2; pi. 66, lig. 15." 

 Loc. (irand h'apids of the Saskatchewan, etc., Canada. 



Conchidium exponeum Hall and Clarke. ISTiagara (Sil.). 



Cuuchiilium exitoueus Hall and Clarke, Pal. Ts'ew York, VITI, Pt. II, 1895, j)l. 66, 



Iigs. 6-9. 

 Loc. Louisville, Kentucky. 



Conchidium georgiae Hall and Clarke. Clinton (Sil.). 



Conchidium georgia- Hall and Clarke, Pal. New York, VIII, Pt. II, 1895, p. 369, 



pi. 66, figs. 18, 19. 

 Loc. Trenton, Georgia. 



Conchidium greenei Hall and Clarke. Niagara (Sil,). 



Conchidium greenii Hall and Clarke, Pal. New York, VIII, Pt. II, 1895, pp. 235, 



368, pi. 66, figs. 20-22. 

 Loc. Near Milwaukee, Wisconsin. 



Conchidium knappi (Hall and Whitfield). N^iagara (Sil.). 



Pentamerus knappi Hall and Whitfield, Twenty-fourth Rep. New York State 



Cab. Nat. Hist., 1872, p. 184.— Nettelroth, Kentucky Fossil Shells, Mem. 



Kentucky Geol. Survey, 1889, p. 55, pi. 28, figs. 1-4. 

 Pentamerus? knappi Hall and Whitfield, Twenty-seventh Rep. New York State 



Cab. Nat. Hist., 1875, pi. 10, figs. 10-12. 

 Conchidium knappi Hall and Clarke, Pal. New York, VIII, Pt. II, 1893, p. 235, 



pi. 64, figs. 11-13. 

 Loc. Louisville, Kentucky 



Conchidium knighti (Nettelroth). ?Corniferous (Dev.). 



Pentamerus knighti Nettelroth (non Sowerby), Kentucky Fossil Shells, Mem. 



Kentucky Geol. Survey, 1889, p. 57, pi. 29, figs. 1, 2, 17. 

 Conchidium uettelrothi Hall and Clarke, Pal. New York, VIII, Pt. II, 1893, 



p. 234, pi. 64, figs. 14-16. 

 Loc. Louisville, Kentucky. 

 Oba. This species is very much like C. nysius and may be identical with it (Ana 



says that C. knighti occurs in the Upper Silurian at Arisaig, Nova Scotia). 



Conchidium laqueatum (Conrad). Niagara (Sil.). 



Pentamerus la^ueatus Conrad, Proc. Acad. Nat. Sci. Philadelphia, VII, 1855, 



p. 441. 

 Pentamerus uobilis Emmons, Manual of Geol., 1860, \^. 107, figure. 

 Conchidium laqueatus Hall and Clarke, Pal. New York, VIII, Pt. II, 1893, p. 232, 



fig. 168; p. 234, pi. 65, Iigs. 3-9. 

 Loc. Delj)hi, Indiaua. 



Conchidium littoni Hall. Niagara (Sil.). 



Pentamerus littoni Hall, Pal. New York, III, 1859, p. 262.— Hall and Whitlield, 

 Twenty-fourth Rep. New York State Cab. Nat. Hist., 1872, p. 186;— Twenty- 

 seventh Rep. Ibidem, 1875, pi. 10, figs. 8, 9. — Nettelroth, Kentucky Fossil 

 Shells, Mem. Kentucky Geol. Survey, 1889, p. 58. pi. 27, Iigs. 12, 13. 



Conchidium littoni Hall and Clarke, Pal. New York, VIII, Pt. II, 1895, pi. 64, 

 figs. 9, 10. 



Loc. Hardin County, Tennessee; Louisville, Kentucky, 



