NO. 6 CUSHMAN, MCCULLOCH : LAGENIDAE 301 



EXPLANATION OF PLATE 38 



Figs. 



1-3. Robulus cf. cultratus Montfort, van X 14, p. 296. 

 4-7. Robulus orbicularis (d'Orbigny). X 33, p. 296. 

 8. Robulus limbosus (Reuss). X 33, p. 297. 



In all specimens, a, side view; b, apertural view. 



