THIRD LECTURE. 



SOME PROBLEMS OF ANNELID MOR- 

 PHOLOGY. 



By EDMUND B. WILSON. 



I SHALL endeavor in this address to consider, in an 

 elementary way, some of the broader morphological 

 questions that are suggested by a study of the develop- 

 ment of annelids. It is a subject that has a very special 

 and technical side ; yet it is also, as I shall try to show, 

 a subject that at every step suggests wider and deeper 

 problems, some of which extend so far beyond the limits 

 of the particular group of annelids as to stand among the 

 most interesting general questions of comparative zool- 

 ogy. They are, moreover, questions which I believe may 

 be made intelligible and suggestive to those who are not 

 specialists — who, I had almost said, are not even zoolo- 

 gists. To this end, however, it is of primary importance 

 to indicate the point of view from which the subject is 

 considered and the pathway by which it is approached. 

 And hence I may perhaps be pardoned for a few intro- 

 ductory remarks on the purposes and methods of morpho- 

 logical inquiry, and the considerations that lend interest 

 to the group of annelids from a general point of view. 



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