26 KONRAD GUENTHER, 



35) Wheeler , The maturation , fecundation and early cleavage of 



Myzostoma glabrum Leuck., in: Arch. Biol., V. 15, 1898. 



36) Wilson, Experimental studies in cytology, I., in : Arch. Entw.-Mech., 



V. 12, 1901. 



37) Wilson-Mathews, Maturation, fertilization and polarity in the 



Echinodenn egg, in: J. Morph oL, V. 10, 1895. 



