W. G. VanNume—EnihryoIoyij of EustylocJius. 297 



23. Van der Stricht, O. — Origine des parties constituantes de la figure achro- 

 matiqiie de Thysanozoon Brocchi. Verhandl. der Anat. Gesellscli. 1894. 



34. Van der Stricht, 0. — Le premier ampliiaster de I'ovule de Thysanozoon 

 Bi'occhi. Une figure mitosique peut-elle retrograder ? Bibliograpliie ana- 

 tomiqtie. No. 1, 1896. 



25. Van der Stricht, 0. — Anomalies lors de la formation de Tamphiaster de 



rebut. Bibliograpliie anatomique, No. 1, 1896. 



26. Van der Stricht, O. — La maturation et la fecondation de I'ceuf de Thy- 



sanozoon Brocchi. Associat. fran§aise pour I'avancement des sciences. 

 Congres de Carthage, 1896. 



27. Van der Stricht, O. — Les ovocentres et les spermocentres de I'ovule de 



Thysanozoon Brocchi. Verhandl. d. Anat. Gesellsch. in Gent. 1897. 



28. Van der Stricht, O. — La formation des deux globiiles polaires et I'appara- 



tiou des spermocentres dans I'oeuf de Thysanozoon Brocchi. Archives de 

 Biologic. Vol. XV, pt. 3, Oct., 1898. 



29. Verrill, a. E. — Marine Plauarians of New England. Trans. Connecticut 



Acad. Vol. viii, 1893. 



30. Wheeler, W. M. — The maturation, fertilization and early cleavage of Mysos- 



toma glabrum Leuckart. Archives de Biologie. Vol. xv, 1897. 



31. Wilson, E. B. and Leaming, E. — An atlas of the fertilization and karyo- 



kinesis of the ovum. 1895. 



32. Van der Stricht, O. — Etude de plusi^res anomalies interessantes lo* de la 



formation des globules polaii'es. Etude de la sphere attractive ovulaire ^ 

 I'etat pathologique, etc. Livre jubilaire dedie a Charles Van Bambeke. 

 Brussels. 1899. 



EXPLANATION OF PLATES. 



With the exception of Figs. 30, 31, 41, 42 and 43, all the figures were drawn 

 with the aid of a camera lucida. 



In illustrating the development of the egg, I have avoided making up figures 

 by combining into one drawing structures which appear in different sections in 

 the prejjaration, preferring to reproduce more than one section where this is 

 necessary. 



The preparations from which the figures of sections were drawn were made 

 with corrosive-acetic solution and stained by Heidenhain's iron-haematoxylin 

 method. 



To this Figs. 1 to 5 inclusive, also 11, 25, 26, 27 and 36 are exceptions. These 

 were preserved with picro-acetic solution, which, as mentioned in the descriptive 

 part, renders the yolk globules inconspicuous, but brings out the reticulum of 

 the cytoplasm strongly. 



Any other exceptions are mentioned in describing the individual figures. 



All represent the eggs or embryos of Eustylochus eUipticus (Girard) Verrill, 

 unless otherwise mentioned. 



