THE EMBRYOLOGY OF THE BIRD S LUNG 



471 



Dissoiira and other birds and also as occurring infrequently in 

 the chick. At the base of the recurrent bronchi of the posterior 

 intermediate and of the accessory sac is an enlargement or pocket 



Cerv.Sc. 



AJntSc. 



Fig. 21 Latero-mesial view of the left lung and air-sacs of an embryo of twelve 

 days incutation. The air-sacs exhibited include the lateral and mesial moieties 

 of the interclavicular and an accessory sac between the posterior intermediate and 

 the abdominal sacs. Recurrent bronchi from the posterior three sacs are shown. 

 Similar bronchi are present on the anterior intermediate and lateral moiety of 

 the interclavicular but hidden from view. 



(Basaltasche) , which Schulze has pointed out as a characteristic 

 structure at the base of the reciuTent bronchi of the different 

 air-sacs. 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 19, NO. 3 



