Plate !)4. 



Fig. 1. FliiUiud triquftra. X 10. D523(). o and 6, opposite sides; r, apertural view. 



2. Flintina bradyana. X 20. D5134. 



3. Massilina arenaria. X 10. D523(). a, side view; b, apertiiral view. 



4. Massilina dwrandii. X 20. a and b, opposite sides; c, apertural view. 



583 



