132 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxv. 



EXPLANATION OF PLATES. 

 Plate XXIX. 



Fig. 1. Streptostyla bartschii Dall ; length 32 mm. ; p. 178. 



2. Gcelocentrum (Crossostephanus) palmeri Dall and Bartsch; exterior, 



with part of the truncated spire restored; height of shaded portion 

 50 mm. ; p. 177. 



3. Anodonta coarctata Anton ; magnification of umbo to show concentric 



undulate sculpture ; p. 180. 



4. Anodonta coarctata Anton ; length of shell 44 mm. ; p. ISO. 



5. Ccelocentrum (Crossostephanus) palmeri Dall and Bartsch; section 



showing armature of axis; total length 67 mm., the upper whorls re- 

 stored ; p. 177. 



6. Streptostyla toyuca Dall ; alt. 27 mm. ; p. 179. 



7. Euglandina livida Dall ; alt. 61 mm. ; p. 180. 



8. Streptostyla jilitlana Dall ; alt. 23 mm. ; p. 179. 



Plate XXX. 



Fig. 1. Diplodon tcebsteri Simpson ; interior view of left valve ; length 66 mm. ; 

 p. 181. 



2. The same, exterior of right valve. 



3. Lampsilis salinasensis Simpson, showing exterior of right and hinge of 



left valve ; length 69 mm. ; p. 181. 



