OCR Text |
Show 1880.] ANATOMY OF PASSERINE BIRDS. 385 which may or may not be due to individual variation. The antepenultimate ring is apparently incomplete on the right side, or is at least exceedingly reduced (vide fig. 5). The penultimate ring is narrowed, and is closely apposed to the terminal ring throughout except in front, where there is a well-marked subtriangular fenestra. The last tracheal ring is produced downwards in front, hut is ap- Syrinx of Cymbirhynchus, viewed from in front, X 5. Fig. 4. Fig. 5. Fig. 4. The same, X 5, from the side, to show the insertion of the intrinsic syringeal muscle into the middle of the first bronchial semiring. The sternotrachealis is cut short. Fig. 5. The same, X 5, from behind, to show the pessulus. parently incomplete on the left side in front; so that there the penultimate ring is next to the first semiring, in consequence of this disposition. The pessulus is a well-marked, forwardly-directed |