PLATE 35. 



Pnge 



Fig. 1 & 2. Rbynchonella sulcoplicata. 236 



1 a, b. Ventral and front views. 



1 c. Enlargement of the striae. 



2 a, b, c, d. Undetermined forms of Bhynchonella. 



Fig. 3 - 5, & % a - y. Rhynchonella Formosa. 236 



3. i a b c d ef, &• 5, may be young forms of R.formosa, possessing some characters not observed 

 in authentic specimens of that species, but approaching figures 6/, g, h. 



C o - c. Ventral, dorsal, profile, and front views of several individuals of the typical form, 

 with strong plications. 



G f- I. Specimens with finer and more numerous plications. 



6 m - y. Illustrations of specimens which present the ordinary variations of fuU-grown indi- 

 viduals, from the Upper Pentamerus limestone. 



