PLATE 27 
All figures approximately natural size 
Fig. 1. Spisula catilliformis Conrad. Longitude 81 mm. Uni- 
versity of California Collection. Note the hinge of left valve. 
Fig. 2. Spisula catilliformis Conrad. Longitude 112.8mm. Uni- 
versity of California collection. Exterior of left valve.. 
[386] 
