EXPLANATION OF PLATES. 

 Plate 1. 



Fig. 1. Cornuspira foliacea. X 60. a, front view; b, apertural view. 

 2. Cornuspira involvens. X 40. a, front view; b, apertural view. 



Plate 2. 



Fig. 1. Cornuspira foliacea. X 20. a, front view; b, apertural view. 



2. Cornuspira involvens. X 40. a, front view; b, apertural view. 



3. Cornuspira lacunosa. X 30. a, front view; b, apertural view. 



Plate 3. 



Fig. 1. Opthalmidium inconstans. X 65. Irrecular specimen. 



2. Opthalmidium inconstans. X 65. A more regular specimen. 



3. Opthalmidium inconstans. X 135. Optical section of young specimen. 



4. Opthalmidium inconstans. X 65. Optical section of adult specimen. 



5. Opthalmidium tumidulum. X 33 (after Brady). 



6. Spiroloculina dcpressa. X 65. a, side view; b, apertural view. 



7. Spiroloculina depressa. X 35. a, front view; b, apertural view of thicker 



specimen. 



8. 9. Spiroloculina dcpressa. X 35. Apertures of adults. 

 10. Spiroloculina dcpressa. X 80. Aperture of young. 



Plate 4. 



Fig. 1. Spiroloculina canaliculata. X 25. a, front view; b, apertural view. 



2. Spiroloculina canaliculata. X 35. Apertural view. 



3. Spiroloculina canaliculata. X 80. Apertural view of young. 



4. Spiroloculina grateloupi. X 25. a, front view; b, side view; c, apertural 



view. 



5. Spiroloculina grateloupi. X 35. a, front view; b, apertural view. 



Plate 5. 



Fig. 1. Spiroloculina acutimar go. X 35. 



2. Spiroloculina tenuimargo. X 65. a, front view; b, apertural view. 



3. Spiroloculina tenuimargo. X 120. a, front view; b, apertural view. 



4. Spiroloculina millettii. X 65. a, front view; b, side view; c, apertural view. 



5. Spiroloculina nuda. X 65. a, front view; 6, side view; c, apertural view. 



Plate 6. 



Fig. 1. Spiroloculina costifera. X 35. a, front view; b, apertural view; c, section. 



2. Spiroloculina costifera. X 30. a, front view; b, apertural view. 



3. Spiroloculina costifera. X 35. End view of another specimen. 



Plate 7. 



Fig. 1. Spiroloculina unicostata. X 135. a, front view; b, side view; c, apertural 

 view. 



2. Spiroloculina unicostata. X 135. a, front view; b, apertural view. 



3. Spiroloculina grata. X 65. Front view. 



4. Spiroloculina grata. X 75. Optical section. 



5. Spiroloculina grata, var. angulata. X 30. a, front view; 6, apertural view. 



99 



