PLATE 32. 
Page 
ig. 1 a - z , & 2 a - d . Rhynchonella pyramidata. 229 
1 a - d. Young individuals of this species. 
1 e - z. Illustrations of the varying forms of this species, from those of medium size to the 
largest and most gibbous forms that have been observed. 
2 a. A cast of the ventral valve of this species, showing the muscular impression smaller than 
in R. nucleolata, Plate xxxi, fig. 2 x. 
2 b. A cast of the dorsal valve of the same species. 
2 c. Interior of the ventral valve, which partially preserves the form of the muscular imprint . 
