52 The Development of the Lungs 
ably beyond that of the last reconstruction. With reference to the smaller 
buds, however, it is impossible either in sections or in clear specimens 
to determine definitely their course and final relationships. Neverthe- 
less, as shown in these specimens, the bronchial tree evolves along the 
same lines. The tendency for the tips of the wings of the lungs to fold 
ventralwards around the heart and liver also becomes more exaggerated 
than in the case of the lung of a 18.5 mm. pig. 
With the exception of the smaller buds, following is a tabulation of 
the main branches of the lung at this age. 
TRACHEA. 
1b, ae 
(2) DI. 
(3) D-L-M-L. 
(2) VS. 
(3) DS-LI-LI-D. 
Right stem bronchus. Left stem bronchus. 
1b PA, Tere 
(2) DI. (2) Apical. 
(3) D-I-D. (3) D-L-M-D. 
(2)04T. (2) eLE: 
(3) VI-DS-I. (3) DS-VI-DI-DS. 
Ware 
(2) cE 
(3) De 
(2) VS. 
@invwae 
1D, 2s 1057 
(2) UM. (2) M. 
(3) 8S. 
(2) L. (2) SD. 
(2) M. (2) L£. 
Tiere Ib, By 
(2) V. (2) D. 
(2) 5D: (2) V. 
(2) SV. @)ee 
(2) D. (2) S. 
We ok Wars 
(CA Op (2) 8. 
(2) M. (2) M. 
1D), Drs: 
(2) M. (2) M. 
(2) Z. CANE: 
(2) M. 
L. 4. L. 4. 
C2) V7. (2) D. 
