ENTRY OF ZOOXANTHELLE INTO OVUM OF MILLEPORA. 707 
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pora, with a short Essay on the Fragmentation of the — 
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EXPLANATION OF PLATE 18, 
Illustrating Mr. Joseph Mangan’s paper on “The Entry of 
Zooxanthelle into the Ovum of Millepora, and some 
particulars concerning the Meduse.” 
Fie. 1.— Oogonial cell from the medusa of Millepora at a period 
prior to the formation of ova. x 1000. 
Fig. 2.—An early stage in the growth of an ovum. The nuclei of the 
surrounding oogonial cells undergo dissolution, fusion with the ovum 
taking place subsequently. x 500. 
