EXPLANATION OF PLATE XXXVI. 



Page 



FIG. 1. Productua costatus 51 



la. Ventral view. 

 Ib. Dorsal view. 

 Ic. Side view. 



Carboniferous, Upper Coal Measures. 



FIG. 2. Productus symmetricus 48 



2a. Side aspect. 

 2b. Ventral aspect. 



Carboniferous, Upper Coal Measures. 



FIG. 8. Productus costatus? 51 



3a. Ventral view. 

 3b. Dorsal aspect. 

 3e. Side view. 



Carboniferous, Upper Coal Measures. 



FIG. 4. Productus semireticulatus 50 



4a. Ventral aspect. 

 4b. Dorsal view. 

 4c. Side view. 



Carboniferous, Upper Coal Measures. 



