HISTOGENESIS AND MORPHOGENESIS OF THE THO- 

 RACIC DUCT IN THE CHICK; DEVELOPMENT OF 

 BLOOD CELLS AND THEIR PASSAGE TO THE BLOOD 

 STREAM VIA THE THORACIC DUCT 



ADAAI M. MILLER 



The Analomical Laboratory of Columbia Univernily 



TWENTTY-EIGHT FIGURES (SEVENTEEN PLATEs) 



I. INTRODUCTION 



The study of the development of the jugular lymph sac in the 

 chick, the result of which was published in this Journal/ (1) led to 

 the investigation also of the developing thoracic duct and the 

 means whereby its communication with the lymph sac is estab- 

 lished. This investigation has been carried on with the advice 

 and under supervision of Dr. Huntington and in the light of his 

 recent work on reptiles (2) and the cat (3). 



Within the past few years different investigators have shown 

 that in the frog (4), (5), the chick (1), (8), the rabbit (6), the cat (9), 

 and in man (7) each jugular l>Tnph sac develops directl}^ from a 

 venous capillar}^ network adjacent to the junction of the early 

 precardinal with the postcardinal vein to form the duct of Cuvier. 

 It has also been pointed out by Huntington (14) that the jugular 

 lymph sacs, regarded as of venous origin, constitute the connecting 

 links between the hemal vascular system and the general system 

 of lymphatic vessels. 



The origin of the systemic h'mphatic vessels is a problem on 

 which investigators are sharply divided. A summary of the 

 different views, including the bibliography, can be found on pages 

 10-13 of Huntington's monograph in the Memoirs of The Wistar 

 Institute (3). 



^ References, by number, will be found on page 162. 



131 



THE AMERICAN- JOURNAL OF ANATOMY, VOL. 15, NO. 2 

 SEPTEMBER, IQl."? 



