Pleurotoma bicarinata, xxxiv, 218.

*— cancellata, xl, 98.f

— decussuta, xxxvi, 390.

Pleurotomaria, xlvii, 367f, 368f, 376.f

*— lenticularis, xlvii, 365.f

*— pervetusta, xlviii, 300.f

*Polythalamia, fossil, from the Upper Mississippi, J. W. Bailey, xli, 400.f

*—, Petersburg, Va., J. W. Bailey, xlv, 313.

*—, in the U. States, J. W. Bailey, xlviii, 340.f

*Producta from St. Louis, xliii, 18,f