iv Preface 



While the first three chapters, that deal with some ana- 

 tomical, developmental, and physiological facts, may re- 

 quire closer attention than some of the others, they are de- 

 signed in part to make clearer several subjects treated sub- 

 sequently. That on anatomy has been made as simple 

 as possible, and the illustrations are new. The short ac- 

 count of a few ciliary mechanisms in the third chapter is 

 from my own observations, and previously I have pub- 

 lished only those on Venus. It may be that even the 

 small part of my cilia work here presented will be of some 

 interest to biologists, for the subject itself is practically 

 new. 



A relatively large amount of attention has, of course, 

 been given to the oyster. My own interest in the form 

 began nearly twenty years ago, my attention being 

 directed to it by the late Professor W. K. Brooks, the 

 great naturalist and great teacher, who will always be 

 remembered in Maryland as the father of oyster culture. 

 My first efforts, made together with another of Dr. 

 Brooks' pupils, were directed toward a solution of the 

 problem of rearing the swimming embryo in small in- 

 closures to the stage in which it became attached, and in 

 spite of the ingenuity of my friend, we failed dismally. 

 For that reason I write with some feeling the chapter 

 on rearing the oyster from the egg. I may perhaps be 

 allowed to state that from many wanderings along our 

 coast, I have been enabled to gain a more or less exten- 

 sive personal knowledge of oyster culture and familiarity 

 with parts of the oyster field described. It has seemed 

 to me that the person who eats oysters — and who does 

 not? — might be interested not merely in the manner of 

 their production and preparation for market, some de- 

 scriptions of which have appeared, but also in the oyster 



