CLAMATORES. 
169 
SECTION II. CLAMATORES. SONGLESS BIRDS. 
Inferior larynx provided with less than five pairs of muscles. The sterno-trachealis 
has its origin below the broncho-trachealis. 
Birds in this Section lack the complicated singing apparatus found in those which are 
placed under Oscines. These last named birds have five pairs of vocal muscles in addition 
to the sterno-trachealis which may he considered as a sixth pair, for they not only support 
the trachea hut, by drawing it downward, thus relaxing the tympaniform membrane, aid 
in producing sound. 
I have given life-sized drawings of the inferior larynx of a Crow in Plate VI, figs. 1 
to 4, in order that students may understand the various parts. Fig. 4 shows a view from 
the lower side; 0, is a portion of the trachea and B, the bronchial tubes which extend to 
the lungs. The muscles which are deeper in color, are as follows: Bt, broncho-trachealis; 
Bp, broncho-tracheals posticus. Fig. 3 exhibits a side view with the same figures ap¬ 
plied to the same parts as far as explained. The broncho-trachealis is better defined and 
its divisions into the broncho-trachealis anticus, B, and posticus, Bp, is very clearly seen. 
The broncho-trachealis brevis is given at Bb, the bronchialis posticus at BB, which with 
the bronchialis anticus, BBa, make up the number of vocal muscles; their counterparts 
being on the opposite side. It is observable that the sterno-trachealis has its tracheal or- 
. igin below the division of the broncho-trachealis; the other extremity being attached to 
the costal process of the sternum, seen in fig. 5, Cp. The exact point from which this 
muscle emerges from the trachea is of great importance in determining in which section 
of the order Insessores any particular species is to be placed, for, in all birds which only 
have the power of modulating their voices to a limited extent, this muscle will be found 
to originate on the trachea quite above the broncho-trachealis. This will be further il¬ 
lustrated in a future plate in which I purpose giving drawings of the larynx of some mem¬ 
ber of Section II. 
The other accessories for producing melodious sounds are the tympaniform membrane 
which stretches across the under side of the upper portion of the bronchial tubes, fig. 2, 
M, and the semilunar membrane, shown in fig. 1, which is a section of the larynx, at S. It 
is supported by the os transversale, T, a slender bone which crosses the interior of the tra¬ 
chea. The office of the leryngeal muscles is to tighten these two membranes, which then 
vibrate and produce sound. 
FAMILY I. TYRANNIDJE. THE TYRANT FLYCATCHERS. 
Bill, more or less triangular inform, wider than high at base, and the upper mandible is abruptly curved at lip which is 
notched. Nasal and loral region at base of upper mandible provided with stiff bristles which also very often occur on the chin. 
Sternum, broad with high keel. 
This is a ]arge family with dull colors, occasionally relieved by yellow below or by bright markings on the crown. 
The differences between the various genera are slight, although constant. I have made some changes in the arrangement 
of the genera, based mainly upon anatomical characters. The tympaniform membrane is always present but, although I 
have found the os transversale in all that I have examined, yet I have never seen the semilunar membrane. The coracoids 
are short, but are set on at an angle causing the furcular to be well arched, and its terminal process is short. 
*22 
BIRDS OF FLORIDA. 
