THE ANATOMY OF BIRDS. — PNEUMATOLOGY. 207 
0, p, trachea, or windpipe; q, inferior larynx, or syrinx; r, 7, right and left bronchus: ss, ss, contractor muscles 
of trachea; ¢, ¢, lungs, with wu, w, apertures communicating with thoracic air-cells ; v, v, v, three pairs of muscular 
slips answering to arudimentary diaphragm; 1, 2,3, 4,5, 6,7, as many ribs. —2. Hyoid bone; a, glosso-hyal, tipped 
with cartilage, its posterior horns being cerato-hyals proper; 0, basi-hyal; c, basi-branchial proper, commonly 
called uro-hyal; d, d, cerato-branchials proper, commonly called apo-hyals ; e, e, epibranchials proper, commonly 
called cerato-hyals, tipped with cartilage, 7,7. —3. Glottis, or opening of trachea in the mouth; a, base of tongue; 
b, 6, horns of hyoid bone ; c, rima glottidis, cleft or chink of the glottis; d,a triangular vacuity ; ¢, an elastic liga- 
ment; d and e represent an epiglottis ; 7, f, a papillose surface. —4. Larynx viewed from before (below); a, thy- 
roid bone or cartilage.—5. Larynx viewed from behind (above); a, thyroid bone; b, b, its appendages; c, cricoid; 
d, d, arytenoids; e, e, anterior border of thyroid, to which d, d are connected by two arytenoid ligaments. —6. 
Larynx viewed from right side; a, thyroid; 6, appendage ; ¢, cricoid; d, arytenoid; 7, /, cartilage attached to ary- 
tenoid; g,a tracheal ring. —7. Larynx viewed from behind; a, thyroid; 0, b, its appendages; c, cricoid; d, d, ary- 
tenoids. — 8, 9,10, 11,12. Muscles of the larynx; 1,1 (fig. 8), thyro-hyoids; 2, 2 (fig. 9), thyro-arytenoids, or openers 
of the glottis; 3,3 (fig. 10), oblique arytenoids; 4, 4 (fig. 11), thyro-cricoids; 5,5 (figs. 11 and 12), posterior thyro- 
cricoids. —13. Bifurcation of trachea; aba, last entire tracheal ring. —14. Last entire tracheal ring, viewed from 
below, crossed by the pessulus.—15. Bifurcation of trachea, and bronchi, viewed from below; a, pessulus, the 
bolt-bar, or ‘‘ bone of divarication ’’; 6, b, next succeeding tracheal half-rings. —16. a, b, c, d, inferior laryngeal 
or syringeal muscles, not well made out in this figure; see text. But the typical oscine arrangement (acromyo- 
dian) is perceived, inasmuch as anterior (a) and posterior (d@) intrinsic muscular masses go to ends of the first 
tracheal half-ring, at b and c ; the extrinsic slip e passing to sternum; compare fig. 1, at g. —17. Trachea, etc., of 
the nightingale, nat. size. (Compare figs. 3, 67, 72, 78, 74.) 
The Song of Birds unlocks the great secret of Genesis to those who can hear the key- 
note. It is the closest approach, in animate nature, to the ringing of the hydrogen bells in the 
physies of light. The musical instrument figured (101, 17) is the identical pipe the ‘‘ great god 
Pan” first fashioned for a legacy to all time, as so sweetly said by Mrs. Browning : — 
“He tore out a reed, the great god Pan, 
From the deep cool bed of the river. 
The limpid water turbidly ran, 
And the broken lilies a-dying lay, 
And the dragon-fly had fled away, 
Ere he brought it out of the river. 
““« This is the way,’ laughed the great god Pan, 
(Laughed while he sate by the river!) 
The only way since gods began 
To make sweet music, they could succeed.’ 
Then dropping his mouth to a hole in the reed, 
He blew in power by the river 
“Sweet, sweet, sweet, O Pan, 
Piercing sweet by the river! 
Blinding sweet, O great good Pan! 
The sun on the hill forgot to die, 
And the lilies revived, and the dragon-fly 
Came back to dream on the river.’’ 
. 
But the sad sequel, felt by Keats, when poor Psyche has seen and known, and Eros has 
found his wings : — 
“*So did he feel who pulled the boughs aside, 
That we might look into a forest wide, 
To catch a glimpse of Fauns, and Dryades 
Coming with softest rustle through the trees; 
And garlands woven of flowers wild and sweet, 
Upheld on ivory wrists, or sporting feet: 
Telling us how fair trembling Syrinz fled 
Arcadian Pan, with such a fearful dread. 
Poor Nymph, — poor Pan, —how he did weep to find 
Naught but a lovely sighing of the wind 
Along the reedy stream! a half heard strain 
Full of sweet desolation, balmy pain.” 
The blessed blue-bird, ‘bearing the sky upon her back,” is burthened with the same 
“light load of song ” — 
