380 



Bronchial left: This is the converse of the preceding type and 

 the description given above also applies to this type (Fig. 5). 



Double bronchial: Here we find that the tracheal cartilage 

 fails to enter the carina and that there is a bar of cartilage on either 

 side of the carina derived, respectively, from the first right and left 

 bronchial cartilages (Fig. 6). 



Mixed: I have placed in this subdivision those cases where a 

 definite classification could not be made and also those cases in which 



Fig. 4. Bronchial right. Fig. 5. Bronchial left. Both of these figures represent 

 typical specimens. 



Fig. 6. Double bronchial. The first right and the first left bronchial cartilage 

 enters the carina on its respective side. 



the anterior part of the carina contained a very small amount of car- 

 tilage derived either from a tracheal or bronchial ring, or from any 

 of the above combinations; the posterior portion of the carina being 

 membranous. In one instance the cartilage entering the carina was 

 derived from a small wedge-shaped piece which was independent of 

 either tracheal or bronchial ring (Fig. 7) ; it appeared to be a detached 

 tracheal spur. 



Membranous: In this type no cartilage enters the carina (Fig. 8). 



Ti& 7. 



Fig. 7. In this case the carina is formed in a peculiar manner. A small wedge- 

 shaped piece of cartilage independent of any connection with either tracheal or bronchial 

 cartilage enters the carina. 



Fig. 8. Membranous. Note the very irregular arrangement of the cartilages and 

 that none of them enter the carina. 



