1877.] 185 [McCrady. 



of the protembryo. There can hardly be drawn from the observa- 

 tions made any other conclusion than that the protembryo is a small 

 mass of undifferentiated and homogeneous protoplasm; in short, an 

 amoeboid protozoon, which in due course possesses itself of the 

 whole yolk mass as food. To speak more particularly, observing the 

 difference introduced by Hseckel between Amoeba and the non- 

 nucleated forms which he has called Monera, the protembryo is, 

 strictly speaking, a Monera, specially conditioned for the develop- 

 ment of that organic form from which it originated. How little such 

 a Monera may possibly differ from those which are found free in na- 

 ture, we conceive, upon reflecting that the complete life history of no 

 Monera or Amoeba is really known, and it remains to be determined 

 whether they are not all protembryonic stages of higher organisms, 

 either animal or vegetable. The history of Myxomycetes, alone, 

 shows how directly an amoeboid form may pass into a distinctly veg- 

 etable structure. 



Again, it seems to me that my interpretation of the ovum and of 

 the spermatozoon as protozoan demats is not likely to be invalidated ; 

 and I cannot but regard all protozoa as, strictly speaking, oozoa, or 

 animal forms in which the individual, or demat, is the sexual 

 product. 



Prof. McCrady also read a paper on the "Diencephalic 

 Canal" of Vertebrates.* 



A second valuable gift of books from the Hon. George B. 

 Emerson was announced, and a vote of thanks to the donor 

 passed. 



A nearly complete set of the publications of the Novara 

 Expedition, presented by the •' K. K. Ministerium far Cultur 

 und Unterricht " of Austria was also exhibited. 



