45 6 



HEM1AULUS. 



The figures in the text represent Hemiaulus bifrons {Ehr. ?) Grun. (fie*. 

 182) from the Nottingham deposit; Trinacria Regina Heib. (fig. 183); 

 Solium exculptum Heib. (fig. 184) and Corinna elegans Heib. (fig. 185), the 

 three latter being found in a fossil state in the " Moler " of Mors. 



a. l>. 



Fig. 182. Hemiaulus bifrv/is. 

 a. Valve view. l>. Girdle view. 



a. b. 



Fig. 183. Trinacria Negri i a. 

 a. Girdle view. /. Valve view. 





b. c. 



Fig. 184. Solium exculptum. 

 a. Girdle view. /'. Valve view. c. Filament. 



