PLATE 4 



Page. 



Fig. 1. Inoceramus howelli 284 



a. View of right side ; test removed. 



Z>. Front view of the same. 



c. Left valve of another example. All natural size. 



FlG. 2. EUSPIRA COALYILLENSIS 310 



a. Side view ; restored from several more or less imperfect examples. 

 o. Apertural view of the same. Natural size. 



Fig. 3. Ostrea (Alectryonia) bellaplicata 276 



a. View of the convex valve. 

 Z>. Side view of the same example. Natural size. 

 See, also, Plate 8, figs. 2 a and o. 



Fig. 4. Palitjrus pentangulatus 302 



a. Side view of broken example ; showing also the matrix of the' 



missing portion. 

 6. Transverse section of the same. Enlarged. 



