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 gills 

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



