10 MUSEUM OF COMPARATIVE ZOOLOGY. [Apr. 



I cannot close this enumeration of the work accomplished 

 within the last year at the Museum, without alluding also to 

 the efficient assistance I have received from Dr. Wilder, in my 

 investigations on Selachians. The farther I advance in the 

 work of organizing the Museum as a systematic representation 

 of the present state of our knowledge of the animal kingdom, 

 the more am I satisfied of the deficiencies in the present mode 

 of arranging public. collections ; the more do I see how little we 

 reproduce in our museums the most important results of modern 

 science. The mere accumulation in systematic order of select 

 specimens from given classes, families, genera, &c, has after all 

 little intellectual value, and does not in any way represent the 

 progress of our investigations. Zoology, comparative anatomy, 

 embryology and paleontology are only parts of one great system, 

 combining under different heads our knowledge of the affinities, 

 the structure, the mode of growth and the order of succession of 

 animals through all times and in their past and present distri- 

 bution upon the surface of the globe. In order to represent 

 these different aspects of the subject in their connection with 

 one another, it is necessary to combine whole specimens of 

 living animals, anatomical preparations, embryological series 

 and fossil remains in the same case, or on the same shelf, in 

 such intelligent relation that they shall illustrate each other, 

 instead of isolating them in separate museums, as is usually 

 done. In order to test such a synthetic arrangement as I 

 have described, and as I wish to see carried out for all classes 

 of the animal kingdom, I selected the Selachians as one which, 

 from its limited number, taken in connection with its existence 

 through all geological periods, would give us the materials for 

 testing such a comprehensive arrangement with greater ease 

 than any other more numerous and diversified class of animals. 

 For the past two years Dr. Wilder has been assisting me in 

 making such preparations of the Selachians of our coast as 

 would enable me to determine what are the anatomical charac- 

 teristics of that class, and by inference those of the other classes 

 of Vertebrates. If I mistake not, this attempt will result in a 

 complete remodelling of Museums. The largenumber of spec- 

 imens of sharks and skates necessary for this investigation have 

 been freely supplied by Capt. Atwood, of Providence, Mr. Edward 

 Johnson, of Nahant, and Mr. Everett, of Swampscott. 



