/IDemotrs of tbe flDuscum of Cojnparatlve ZoQIoq'S 



AT HARVARD COLLEGE. 

 Vol. XL. No. 9. 



STUDIES FROM THE NEWPORT MARINE LABORATORY. 



Communicated by Alexander Agassiz. 



XVI. 



THE DEVELOPMENT OF 0S8E0US FISHES. 



II. 



THE PRE-EMBRYONIC STAGES OF DEVELOPMENT. 



PART SECOND. — THE HLSTORY OF THE EGG: CLEAVAGE, FORMATION OF THE 

 PERIBLAST, AND DEVELOPMENT OF THE GERM RING. 



BY 



ALEXANDER AGASSIZ and C. O. WHITMAN. 



WITH ELEVEN PLATES. 



CAMBRinGE, U.S.A.: 



PrtnteD for tbe /Duseum. 



April, 1915. 



