TO 



TROFESSOR JOSEPH LEIDY, M. D., LL. D., 



Pr.ESIDENT OF THE ACADEMY OF NATCKAL SCIENCES OF nilLADELrniA, 4C., 



WHOSE PROFOUND RESEARCHES HAVE SO LARGELY TENDED TO DEVELOP 



THE SCIENCE OF BIOLOGY, 



THIS VOLUME IS RESPECTFULLY DEDICATED. 



A. H. 



