GASTROPODA— PLEUR0T0MARIID2E. 



629 



XXVII. Raphistomina Ulrich and Scofield. 



Depressed conical, umbilicate, with sharply angular and carinate 

 whorls, the carina projecting over the moderately impressed suture ; 

 growth lines below carina at first curving backwards ; no notch or 

 band. Cambric-Ordovicic. 

 84. R. (?) attleboroughensis Shaler and Foerste. (Fig. 850.) 



Cambric. 



Minute, low-spired ; shoulder whorls flat or faintly concave, 

 base of whorls rather flat, shoulder angle not very sharp. 



Lower Cambric of Newfoundland ? and eastern Massachusetts. 



Fig. 851. a-d, Raphistoma peracutum [a, \ I ; 6, enlargement of surface; r, d, 

 X2): e-g, Raphistomina lapicida ; h-j, Euomphalopterus Valerius var. obsoletus 

 (After Ulrich and Scof., Pal. Minn. ) 



85. R. lapicida Salter. (Fig. 851, e-g.) Ordovicic. 



Medium-sized, height of spire about equal to height of body of 

 last whorl ; whorls embracing to angle except last one, which 

 occasionally falls below ; peripheral angulation sharp and carinate. 



Black River of Canada and Tennessee. 



XXVIII. Euomphalopteris Roemer. 



Trochoid or subtruncate, broadly umbilicated shells, with the 

 shoulder flat or concave and the body receding, the angle being 



