PLATE III. 



FIG. 1. Acrotrcta papillata, 2i x 2 x 1 mm. Mag. ^ o A narrow ventral valve ; 

 b Same from the side ; c Mould of interior of a ventral valve ; d Dorsal 

 valve ; e Same from the side ; / Mould of interior. From Assise E. Id 

 (Lower Etchemin.) at Boundary brook, Escasonie, N. S. See p. 95. 



FIG. 2. papillata, mut. prima, 2 x 2 x 1 mm. Mag. f ; a Ventral valve ; b Same, 

 side view ; c Mould of ventral. From the Coldbrook Group, Dugald brook, 

 Escasonie, N . S. See p. 73. 



FIG. 3. A papillata var. lata, 2 x 2i x 1 mm. Mag. Y ; a Ventral, mould of interior ; 

 b Same from the side ; c Same from behind. From Assise E. Id (Lower 

 Etchemin. ) at Boundary brook, p]scasonie, N. S. See p. 95. 



FIG. 4. Acrotreta gcinmula, li x li x L mm. Mag. ^ ; a Ventral from behind ; b 

 Same from the side ; c Ventral, mould of interior ; d Dorsal, interior. 

 From Protolenus Beds (C. Ib), Hanford brook N. B. See p. 97. 



FIG. 5. Acrotrcta cf. socialis, \. Seebach 3x3x2 mm. Mag. f (except e. and k.) ; 

 Ventral valve ; b Same from the side ; c Mould of interior ; d Same 

 from the side ; e Apex of the mould, mag. f ; / Dorsal valve ; g Same 

 from the side ; h Mould of interior; i Same from the side ; k Enlargement 

 of surface sculpturing, mag. \? . From Lingulella radulaZone, (St. John Gr : 

 C.2c), McNeil brook, Mira, N. S. See p. 183. 



