RANGE OF THE PELECYPODA 



429 



[Grateful acknowledgments are due to Dr. W. H. Dall, of tlie United States National 

 Museum, for having revised and in large part rewritten the preceding chapter on the Pelecypod.s. 

 It is to be regretted, however, that limits of space necessitated a partial abbreviation of the 

 original text, for which the Editor alone is responsible. TRANS.] 



