SEXUAL SELECTION IN RELATION TO MAN 781 



not doubt that a good violinist would be able to give a cor- 

 rect idea of the gibbon's composition, excepting as regards 

 its loudness." Mr. Waterhouse then gives the notes. Prof. 

 Owen, who is a musician, confirms the foregoing statement, 

 and remarks, though erroneously, that this gibbon "alone 

 of brute mammals may be said to sing." It appears to be 

 much excited after its performance. Unfortunately, its hab- 

 its have never been closely observed in a state of nature; 

 but, from the analogy of other' animals, it is probable that 

 it uses its musical powers more especially during the season 

 of courtship. 



This gibbon is not the only species in the genus which 

 sings, for my son, Francis Darwin, attentively listened in 

 the Zoological Gardens to H. leuciscus while singing a ca- 

 dence of three notes, in true musical intervals, and with 

 a clear musical tone. It is a more surprising fact that 

 certain rodents utter musical sounds. Singing mice have 

 ' often been mentioned and exhibited, but imposture has 

 commonly been suspected. We have, however, at last a 

 clear account by a well-known observer^ the Rev. S. Lock- 

 wood," of the musical powers of an American species, the 

 Hesperomys cognatus, belonging to a genus distinct from 

 that of the English mouse. This little animal was kept 

 in confinement, and the performance was repeatedly heard. 

 In one of the two chief songs, "the last bar would fre- 

 quently be prolonged to two or three; and she would 

 sometimes change from sharp and D, to natural and 

 D, then warble on these two notes a while, and wind up 

 with a quick chirp on C sharp and D. The distinctness 

 between the semitones was very marked, and easily appre- 

 ciable to a good ear." Mr. Lockwood gives both songs in 

 musical notation; and adds that though this little mouse 

 "had no ear for time, yet she would keep to the key of B 

 (two flats) and strictly in a major key. . . . Her soft clear 

 voice falls an octave with all the precision possible; then, at 



« The "American Naturalist," 1872, p. 761. 



