N O T I C E . 



The present number of tlie Memoirs is the first of a series of " Selections from Em- 

 bryological Monographs," which it is proposed to issue as Vol. IX. of the Memoirs of the 

 Museum, so as to give to tlie student in an easily accessible form a more or less com- 

 plete iconography of the embryology of each important group of the animal kingdom. 

 Tliis selection is not intended to be a hand-book, but rather an atlas to accompany any 

 general work on the subject. The plates will be issued in pai'ts, as fast as practicable, 

 each part covering a somewhat limited field, and occasional appendices may be published 

 to prevent the plates from becoming antiquated. 



The quarto illustrations will be accompanied by a carefully prepared explanation, 

 and l)y a bibliography, in octavo, to be made as complete as possible. The Bibliography 

 (by "Walter Faxon) which accompanies this numlier (Crustacea) has been published 

 as No. 6 of Vol. IX. of the Bulletin of the Museum. 



The parts devoted to Echinoderms, Acalephs, and Polyps are well advanced. 



The phenomena connected with the fecundation and maturation of the egg, and tlie 

 history of the formation of the embryonic layers, will be treated in a separate part, 

 without regard to the systematic zoological connection of the observations. 



A number of original drawings will be incorporated with these selections wherever 

 tliey supplement published material. 



The work was planned as early as 1873. I hoped then to publish it with the col- 

 laboration of Dr. A. S. Packard, Jr. Other duties prevented tliis plan from being 

 carried out. In 1875, Professor John McCrady kindly consented to become my col- 

 laborator, but his removal from Cambridge stopped the undertaking in its earliest 

 stages. 



ALEXANDER AGASSIZ. 



Museum of Comparative Zoology, 

 Cambridge, Mass., U. S. A. 



July, 1882. 



