EPARTERIAL BRONCHIAL SYSTEM. 139 



The entire right trunk, carrying its secondary branches A'' 

 and A'\ has shifted cephalad on the stem-bronchus, becoming 

 ** eparterial," while on the left side the trunk maintains its original 

 position below the artery. 



The secondary branch B' on the left side appears reduced. 



The cardiac bronchus is large, arising below the origin of B' 

 from the medial margin of the stem-bronchus. The cor- 

 responding artery reaches the ventral surface of the cardiac 

 bronchus by crossing obliquely meso-caudad over the stem- 

 bronchus below the origin B' . 



VI. Auchenia glama-pacos — Llama-Alpaca. 



Corrosion of bronchial system and pulmonary artery. Co- 

 lumbia University Museum, No. 585. PL XXI. 



The arrangement of the bronchial system on the right side 

 follows in the main the artiodactyl type as represented by 

 Dicotylcs, with certain minor exceptions to be presently men- 

 tioned. The same number and disposition of the main branches 

 is to be noted. 



On the left side further extension cephalad of the apical por- 

 tion of the lung has led to a division of the cephalic trunk A, 

 repeating the one found on the right side. 



The lateral branch A" occupies the position corresponding 

 to the same branch on the right side, below the pulmonary 

 artery. The apical branch A' has migrated cephalad, appearing 

 as an " eparterial " bronchus arising close to the tracheal bifur- 

 cation from the left primar>^ bronchus. 



The arterial distribution is symmetrical ; the vessels accom- 

 panying the branch A' are on both sides derived from the be- 

 ginning of the pulmonary artery, coursing on the ventral aspect 

 of the corresponding bronchus. 



This form, noted already by Aeby, constitutes the type which 

 he describes as *' bilateral eparterial bronchus, tracheal on right, 

 bronchial on left side," 



The cardiac bronchus is also shifted cephalad, arising from 



