302 PROCEEDINGS OP THE ACADEMY OF [1889. 



Bulimorpha nitidula (Meek and Worthen). 



Loxonema nitidulum M. and W., 1860. Proc. Acad. Nat. Sci. 

 Phila., p. 41!."); Polyphemopsis nitidula M. and W., 18(36. Geol. 

 Sur. Illinois, vol. II, p. 874. Upper Coal Measures. 



It seems very probable that this is the same form that was described 

 by Hall as Macrochilus fiisiforme and afterwards, in 1877, changed 

 to M. attenuatum. Should this inference be correct the latter must 

 be regarded a synonym of B. nitidula. Hall's type however was im- 

 perfect and the apertural characters not shown. The confusion has 

 been further increased by a general want of discrimination on the 

 part of some writers, between this and various varietal forms of 

 Soleniseus newberryi (Stevens). 

 Polyphemopsis peracuta Meek and Worthen. 



Eulima peracuta M. and W., I860. Proc. Acad. Nat. Sci. Phila., 

 p. 466 ; Polyphemopsis peracuta M. and W., 1866. Geol. Sur. 

 Illinois, vol. II, p. 375. Coal Measures. 



This species manifestly does not belong to the Bulimorpha group. 



At present, it appears that the original reference of this form to 



Eulima is probably correct. 



