THE EMBRYOLOGY OF THE BIRD S LUNG 



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R.Lg 



Fiji;. 61 Transparency of the lungs of an embryo of 5 days 22 hours incuba- 

 tion. (A) illustrates the chief branches of the pulmonary vein of the left lung. 

 (B) exhibits the pulmonary artery and the pulmonary vein of the right lung with 

 parts of the capillary network connecting the two. Buds of ectobronohi are 

 formed at this stage. 



Fig. 62 Dissection of the lung territory of an embryo of 6| days incubation 

 to show especially the capillary plexus connecting the pulmonary artery and 

 the laryngo-tracheal vein. In other specimens a small vessel leaves the ventral 

 wall of the pulmonary artery and breaks into a capillary network (figs. 12 and 

 14j . Shows also the connections of the pulmonary veins and the laryngo-tracheal 

 veins with the trunk vessel leading into the left atrium of the heart. 



