364 OUTLINES OF CHORDATE DEVELOPMENT 



eal proliferation and in part from sympathetic ganglion cells; 

 the part derived from the peritoneal cells effects secondary con- 

 nections with certain mesonephric components. 



During the fourth day the peritoneal cells in front of the germi- 

 nal epithelia proliferate and extend through the mesenchyme 

 anterior to the mesonephroi and along the dorsal aorta. As 

 these cells multiply they become arranged in definite strands 

 or solid cords; these cords then connect with the renal vesicles 

 of the adjacent portion of the mesonephros. By the eighth day 

 a definite and highly vascular rudiment is established on each 

 side. About this time cells of a sympathetic ganglion located 

 on the antero-dorsal side of the adrenal rudiment, begin to 

 extend into it, penetrating among the primary cords. During 

 the later stages these peritoneal and sympathetic components 

 assume the relations found in the adult adrenal, forming then 

 the cortical and medullary cords respectively. 



REFERENCES TO LITERATURE 



CHAPTERS IV AND V 



ABEL, W., Further Observations on the Development of the Sympa- 

 thetic Nervous System in the Chick. Jour. Anat. Physiol. 47. 



1912. 

 ASSHETON, R., An Experimental Examination into the Growth of the 



Blastoderm of the Chick. Proc. Roy. Soc. 60. 1896. Gas- 



trulation in Birds. Q. J. M. S. 58. 1912. 

 BARTELMEZ, G. W., The Bilaterality of the Pigeon's Egg. A Study in 



Egg Organization from the First Growth Period of the Oocyte to 



the Beginning of Cleavage. Pt. I. Jour. Morph. 23. 1912. 

 BEARD, J., The Development of the Peripheral Nervous System of 



Vertebrates. Pt. I. Elasmobranchii and Aves. Q. J. M. S. 29. 



1888. 

 BELOGOLOWY, G., Zur Entwickelung der Kopfnerven der Vogel. Ein 



Beitrag zur Morphologic des Nervensystems der Wirbelthiere. 



Bull. Soc. Natural. Moscou. 22. 1910. 

 BLOUNT, M., The Early Development of the Pigeon's Egg with especial 



Reference to the Supernumerary Sperm Nuclei, the Periblast and 



the Germ Wall. Biol. Bull. 13. 1907. 

 BRACKET, A., Die Entwickelung der grossen Korperhohlen und ihre 



Trennung von einander (Perikardial-, Pleural-, and Peritoneal- 



