PLATE 10 



Leptaena rhomboidalis Wilckens 



Page ^ 



1-4 Cardinal and profile views of two shells of usual size 

 5, 6 Larger individuals 



Leptaenisca concava Hall 



P.i;e 46 



7 Interior of a ventral valve, x 1 y z 



8, 9 Cardinal and upper views of the ventral valve showing cicatrix of 

 attachment and the umbonal distortion, x 1 y 2 

 10, 11 Similar views of an older shell 



Schizophoria multistriata Hall 



Page 47 



12-18 A series oi illustrations showing the general character of the shells in 

 these beds. Figure 14 is an enlargement of the punctate surface 



Rhipidomella hybridoides Clarke 



Page 47 



19-28 Of these illustrations figures 24, 25, 26 are views of the same 



shell enlarged x 2. Others are natural size 



186 



