190 
COMPARATIVE ZOOLOGY. 
cartilage, to which one end of the cords is attached. The 
will cannot influence the contraction of the vocalizing 
muscles, except in the very act of vocalization. The vo¬ 
cal sounds produced by Mammals may be 
distinguished into the ordinary voice, the 
cry, and the song. The second is the sound 
made by brutes. The Whale, Porpoise, Ar¬ 
madillo, Ant-eater, Porcupine, and Giraffe 
are generally silent. The Bat’s voice is 
probably the shrillest sound audible to hu- 
fig. 159.—Human man ears . There is little modulation in 
Larynx, seen in 
profile; a, half brute utterance. The Opossum purrs, the 
bone ; e, tra- Sloth and Kangaroo moan, the Hog grunts 
ngnsj^epigiot- or squeals, the Tapir whistles, the Stag bel- 
tiB - lows, and the Elephant gives a hoarse trump¬ 
et sound from its trunk and a deep groan from its throat. 
All Sheep have a guttural voice; all the Cows low, from 
the Bison to the Musk-ox; all the Horses and Donkeys 
neigh; all the Cats miau , from the domestic animal to the 
Lion; all the Bears growl; and all the Canine family— 
Fox, Wolf, and Dog — bark and howl. The Howling- 
monkeys and Gorillas have a large cavity, or sac, in the 
throat for resonance, enabling them to utter a powerful 
voice; and one of the Gibbon-apes has the remarkable 
power of emitting a complete octave of musical notes. 
The human voice, taking the male and female together, 
has a range of nearly four octaves. Man’s power of speech, 
or the utterance of articulate sounds, is due to his intel¬ 
lectual development rather than to any structural differ¬ 
ence between him and the Apes. Song is produced by 
the vocal cords, speech by the mouth. 
