PEEFACK 

 IV 



The Memoir on the Embryology of the Starfish, Part I, has been repub- 

 lished substantially as it originally appeared in 1864, in advance of the 

 remainder of the volume. I have added notes in brackets on the points 

 where additions have been made by subsequent investigations for the sake 

 of calling attention to the present condition of the subject, and I beg the 

 reader to remember that it was written thirteen years ago. 



ALEXANDER AGASSIZ. 



Museum of Comparativk Zoology, } 

 Cambkidge, April, 1877. ^ 



