38 
b. Mycetopedina. Foot elongate, enlarged at the end. Shell 
gaping at each end. 
5. Mycetopus. 
1 . M. siliquosus, t. 359. f. 1 . 
C. Shell attached by the outer surface of one valve. Periostraca 
hard, polished. Fluviatile. 
Fam. 7- Etheriadte. 
Mantle edge bearded. Gills two on each side, large, dependent. 
Foot none. Body produced into the cavity of the mantle like a 
foot. Anterior adductor muscle small, linear, or wanting. Lips 
very large, semioval, and attached by the straight edge without 
any free point, as in Muteladce. Shell pearly and blistered within. 
Hinge toothless. Cartilage subinternal, curved. Young shell free, 
like Unio. 
1. Etheria. 
1. E. senegalensis, t. 365. f. 2. 
2. E. Cailliaudi, t. 365. f. 1. 
2. Mulleria. 
1. M. Acostsea (fig. 22). 
Fig. 22 . — Mulleria Acostcea. 
a , the young normal shell on apex. 
