336 



ON THE TRACHEA OF SELEUCIDES. 



intrinsic muscles, the interval comprising 8 tracheal rings, it becomes 

 peculiarly modified, the tube itself becoming slightly dilated and 

 flattened antero-posteriorly, whilst the tracheal rings become broader, 

 and ossified along the middle of their depth, the borders only remaining 



P. Z. S. 1882, 

 p. 334. 



Lower portion of trachea of Seleucides nigra $ , from before. Twice the 

 natural size. 



4, 5,6, 7, 8, 9, 10, 11. Fourth, fifth, &c. (from bottom) tracheal rings, "peculiarly 

 modified. III. Third bronchial semiring, s.t, sterno-trachealis muscle, cut 

 short. 



P.Z. S. 1882, cartilaginous. This ossified part of each ring is slightly concave, so 



p. 333. that when seen laterally the cartilaginous margins project slightly from 



it, the whole ring being thus like a fluted table-napkin ring, when seen 



in section. The intervals between these peculiar rings are very much 



