John P. Munson 337 



position of the nucleus and centrosome respectively. The pole at which 

 the centrosome is located becomes the vegetative pole, due, as I have 

 shown, to the fact that it especially is the center of cytoplasmic growth. 

 The egg axis has no fixed relation to other parts of the ovary. I 

 found this to be true, also, of the Qgg of Limulus. Nor does the. eccen- 

 tricity of the germinal vesicle show any fixed relation to the source of 

 food so far as this can be determined in this Qgg. The egg of Limulus 

 being related to a germinal epithelium rather than to a follicle, was 

 especially favorable for the determination of that question, the source 

 of food being there easily determined. In that Qgg, also, the eccen- 

 tricity of the germinal vesicle bore no constant relation to the source 

 of food. I was led in the study of that Qgg to the conclusion, which 

 I am forced to accept here, that the egg axis is determined from the 

 beginning by the position of the germinal vesicle and centrosome, and 

 that neither gravity nor the topographical relation of the egg to other 

 tissues has any important influence in the matter. 



LITERATURE. 



1. Albrecht, E. — Untersuchungen zur Structur des Seeigeleies. Sitzb. Ges. 



Morph. Phys., Miinchen, 189S. 



2. AuERBACH, L. — Untersuchungen iiber die Spermatogenese von Paludina 



vivipara. Jena. Zeit., Bd. XXX, 1893. 



3. Altmann, R. — Die Elementar Organismen und ihre Beziehungen zu den 



Zellen. Leipzig, 1894. 



4. Die Genese der Zellen. Leipzig, 1887. 



5. Andrews, E. A. — Filose Activities in Metazoan Eggs. Zool. Bull., H, 1. 



6. Balbiani, E. G.— Sur I'origin du follicle et du Noyan vitellim de I'ceuf 



Chez. Les Geophiles. Zool. Anz., Nos. 155 et 156, 1883. 



7. Centrosome et Dotterkern. Journ. Anat. et de la Physiol., No. 2. 



8- Sur la structure du noyau des cellules salivares chez les larves 



de Chironomus. Zool. Anzeiger, 1881. 

 9. Batschli, O. — Ueber die sogenannten Centralkorper der Zellen und ihre 

 Bedeutung. Verh. Naturhist. Med. Ver., Heidelberg, 1891. 



10. Brass, A. — Die Organisation der thierischen Zelle, Halle, 1887. 



11. Brauer, a. — Das Ei von Branchipus Grubii von der Bildung bis zur 



Ablage. Abh. Preuss. Akad. Wiss., 1892. 



12. De Bruyxe, C. — La sphere attractive dans les cellule fixes du tissu con- 



jonctif. Bull. Acad. Sc. de Belgique, XXX. 

 3 3. Burger, O. — Ueber Attraktionsspharen in den Zellkorpern einer Leibesfliis- 

 sigkeit. Anatomischer Anzeiger, 1891. 



14. Was sind die Attractionsspharen und Centralkorper? Anatom- 

 ischer Anzeiger, 1892. 



15. Born, G. — Ueber den Einfluss der Schwere auf das Froschei. Arch. f. 



mikr. Anatomie, XXIV, 1894. 



16. Ballowitz. — Zur Kenntniss der Zellsphare. Arch. f. Anat. u. Phys., 1898. 



