Hyatt.] 54 [March 5, 



egg, and the female pronucleus, that part of the nucleus which 

 remains in the egg after exclusion of the polar globules, (Morph. 

 Jahrb. 1876), thus conclusively proving that the resulting or 

 renovated nucleus was bisexual or married, so far as known, in 

 all eggs. This point certainly tells strongly in favor of the view 

 that the duplex or married character of the segmentation nucleus 

 is an essential preliminary condition for extensive growth by self- 

 division. 



We propose, therefore, for convenience sake, to call the origi- 

 nal undifferentiated generative body the nucleus, and its products 

 respectively the male or masculonucleus, and the female or 

 feminonucleus, reserving the name of spermatozoa and polar 

 globules for the products of the division of the masculonucleus; 

 and the name of maritonucleus or married nucleus for the 

 renovated nucleus of the egg after its union with the male pro- 

 nucleus. This last we shall also more appropriately term the 

 spermonucleus in accordance with its derivation. 



Dr. C. S. Minot was the first to assume that ova and spermato- 

 cysts were essentially bisexual. This author explained the cast- 

 ing off of the polar globules from the egg previous to seg- 

 mentation, and the residuum, or undivided nuclear mass left in 

 the centre, and the parallel case of the production of spermatozoa 

 in the spermatozocyst and the undivided mass left in the centre 

 of the cysts, by means of the Gonoblast theory (Proc. Bost. 

 Soc. Nat. Hist., Nov. 1877, p. 170) } According to this hypothesis 

 the residuum of the spermatocyst is the unused female elements 

 of the bisexual nucleus, equivalent to the active feminonucleus 

 of the egg, while the active spermatozoa are the products of 

 the division of the masculonucleus and are the homologues 

 of the inactive and useless polar globules in the egg. Thus 

 the part useless and resorbed in the male spermatocyst corres- 

 ponds to the active part of the female ovum, while the active 

 part of the male on the other hand corresponds to the inactive 

 and discarded parts of the ovum. The products of the nucleus, 

 masculonucleus and feminonucleus, are thus explained as being 

 in every situation complementary to each other. This theory is 

 consistent, and we do not see how those who consider the double 

 nucleus of Protozoa as bisexual can avoid adopting it, especially, 



i See also Am. Nat., Feb. 1880; and Biol. Centralblatt, 1882, p. 365. 



