EXPLANATION OF PLATE XXXI. 
Stutchburia costata, Morris, sp. 
Fig. 1. Internal cast of a left valve. 
Stutchburia corner essa> Morris, sp. 
,, 2. Internal cast of a left valve. A = crest representing the 
ligainental (?) pit in front of the umbo. 
Stutchburia obliqua , Eth. fil. 
,, 3. Internal cast of a right valve. 
