IV  PREFACE 
fish  bones  by  E.  D.  Reid ;  niollusks  by  Harald  A.  Rehder ;  and  crusta- 
ceans by  Dr.  Waldo  L.  Schmitt  and  Dr.  H.  A.  Pilsbry.  The  mineral 
identifications  were  made  by  E.  P.  Henderson. 
The  drawings,  maps  and-  charts  are  the  work  of  E.  G.  Cassedy, 
Frank  Imrey,  and  J.  W.  Wilson.  Mr.  Cassedy  has  made  the  frontis- 
piece, and  text  figures  1-3,  7,  10-13,  18-22,  24-26;  Mr.  Imrey  has 
made  plates  14,  16,  18,  and  text  figures  5,  8,  14;  and  Mr.  Wilson  text 
figures  4,  6,  9,  15-17,  23.  The  photographs  of  specimens  were  made 
in  the  photographic  laboratory  of  the  United  States  National  Museum 
by  G.  I.  High  tower. 
