In general, the organs of Pecten lie at three different layers, viz., valve, mantle 

 and gills. Figs. 73, 74 and 75, which are one and one-quarter times the natural 

 size, represent the views disclosed as each of these layers is successively cut away. 



Fig. 73. View of Pecten with left valve removed. The gills (g), liver (1) 

 and palps (Ip) are represented in dotted lines as they are seen through the trans- 

 parent mantle. As the left lobe of mantle (m) has been detached from the shell. 

 it has contracted. The right mantle (m) lobe is shown fully extended. 



Fig. 74. View of Pecten with left valve and mantle removed, showing frills 

 (g), palps (Ip), foot (f) and liver (1). 



