CERATOCYPRIS [C. symmetrica] Poulsen 1934,p.38 [Bairdiidae 
by Poulsen; Aparchitidae by Hessland 1949, p.1h8;3 
?Leperditellidae-?Conchoprimitiinae by Hennings- 
moen 1953,pe255,275] Silurian of Greeland. 
CERATOPLEURINA [C. mimiri] Coryell and Johnson 1939,p.221 
([Glyptopleuridae by C&J.] Mississippian of 
Illinois. [= Glyptopleura Girty, by Cooper 1941, 
peh2] 
CERATOPSIS [Beyrichia chambersi Miller 1874,p.234,fig.27] 
Ulrich 1894,p.675 [Beyrichiidae by Bassler & 
Kellett 1934,pe242; Tetradellidae by Swartz 
1936,pe551; Primitiidae-Dilobellinae by Kay 190a, 
pe2e57; Hollinidae-Tetradellinae by Hessland 1949, 
pe 329; Tetradellidae-Tetradellinae by Henningsmoen 
1953,pe216,267.] Ordovician, Ohio. 
CHESTERELLA [C. fissurata] Croneis and Gutke 1939,pe45 
[Kloedenellidae-Kloedenellinae by Henningsmoen 
1953,pe2h3,271] Mississippian of Illinois. 
CHEVROLEPERDITIA [C. chevronalis] Swartz 1949,p.319 
[Leperditiidae-Leperditiinae by Swartz] Ordovician 
or Silurian in well, Early County, Georgia. 
CHILOBOLBA Bonnema 1938,p.104 = Chilobolbina. 
31 
