PLATE 4 



EXPLANATION OF FIGURE 



Fig. 6 Ventral view of the arteries, veins and lymphatics found in the head 

 and pharynx of a seventeen-day steelhead trout embryo; injected embrj-o. P. E. 

 C. 740. 



REFERENCES 



1, Subocular lymph sac 



3', Independent anlagen of the lateral 

 pharyngeal lymphatic which lie ante- 

 rior to the otic communication 



3", Otic lymph sac; anlage of the 

 lateral pharyngeal lymphatic which 

 lies near the caudal end of the oto- 

 cyst and which may establish a com- 

 munication with the precardinal vein 

 at the otic communication 



3'", Cardino-Cuvierian lymph sac; 

 anlage of the lateral pharj-ngeal lym- 

 phatic which lies opposite to the car- 

 dino-Cuvierian junction and between 

 the latter and the otic lymph sac 



5", Anlage of the precardinal lym- 

 phatic which lies contiguous to the 

 otic communication and which es- 

 tablishes a connection with the lat- 

 eral pharyngeal lymphatic 



6, Precardinal or jugular vein 



8, Cranial end of otocyst 



9, Cardino-Cuvierian communication; 

 the point at which the lateral pharyn- 

 geal lymphatic communicates with 

 the precardinal vein in the cardino- 

 Cuvierian district 



10, Lymphatic of the lateral line of 

 the trunk 



14, Dorsal aorta 



15, Hyoidean artery 



16, First efferent aortic arch 



17, Second efferent aortic arch 



18, Third efferent aortic arch 



19, Fourth efferent aortic arch 



20, Caudal end of eye 

 22, Carotid artery 



24, Cardino-Cuvierian junction 

 27, Root of dorsal aorta 



82 



