Report of U. S. National Museum, 1897. -Flint. 



Plate 42. 



Fig. 1. SPIROLOCULINA ROBUSTA Brady. See page 296. 



a. Horizontal Section. /;. Transverse Section. 



Fig. 2 . SPIROLOCULINA ROBUSTA Brady, (transition stages from biloculina compressa.) 



rr.~ or^,^^. See Page 296. 



FIG. 3. SPIROLOCULINA LIMBATA D'ORBIGNY. See Page 296. 



Fig. 4. SPIROLOCULINA PLANULATA Lamarck. See page 297. 



