PLATE 4. 



Page. 

 Fia. 1. INOCERAMTJS HOWELLI 284 



a. Vie-w of right side ; test removed. 



b. Front view of tlie same. 



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



Fig. 2. EuspiBA coalvellensis 310 



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

 i. Apertural view of the same. Natural size. 



Fig. 3. OsTE-EA (Alectryonia) bellaplicata 276 



a. View of the convex valve. 

 i. Side view of the same example. Natural size. 

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



Fm. 4. Pajliukus pentangulatus 302 



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



missing portion. 

 &, Transverse section of the same. Enlarged. 



