1865.] Solater on the Mammals of South America. 605 



this head we must class the pianoforte, the open organ pipes, the softer 

 tones of the human voice, and the horn, which latter forms the link 

 which connects these with instruments with high upper tones. 



Flutes and the wide closed organ pipes approach nearly to the 

 simple sounds. 



That when only the upper tones of the uneven numbers are present, 

 as in the narrow closed organ pipes, strings struck in the middle, and 

 in the clarinet, the sound has a hollow, and if the upper tones are 

 very numerous, a positively nasal character. When the fundamental 

 is predominant the sound is full, but if it is deficient it is thin. On 

 this account the sound of wide open pipes is fuller than that of narrow 

 ones, and the sound of strings struck with a soft hammer, than those 

 struck by a hard one, and the tone of reeds with a resonance tube 

 richer than that of reeds not so furnished. When the upper tones 

 beyond the sixteenth or seventeenth are perceptible the sound is sharp 

 and rough, on account of the discord of the higher tones. The degree 

 of sharpness may vary, if slight it does not prevent the use of such 

 instruments in music. Under this head come fiddles, most reed pipes, 

 the oboe, harmonium, and human voice. These dissonant upper tones 

 are far more prominent in the brass instruments, and they can scarcely 

 be used alone for classical music, but they are of value on certain 

 occasions for their great power in the orchestra. 



THE MAMMALS OF SOUTH AMEEICA. 



By P. L. Sclatee, M.A., Ph.D., F.E.S., Secretary to the Zoological 

 Society of London. 



{With a Plate by Wolf.) 



The Zoological differences between the Old and New Worlds have 

 been well known to naturalists since the time of Buffon, whose theory 

 it was that the animals of America were degraded descendants of 

 those of the Eastern Hemisphere. While there is, no doubt, some 

 sort of truth in this idea — for, where corresponding forms occur, the 

 American is usually less in bulk and feebler in its distinctive 

 characters than its representative in the Old World — it will be 

 better, if we wish to gain a correct view of the Zoology of America, 

 to dismiss altogether from our minds any idea of parallelism between 

 the two Faunas. The northern portion of the Western Hemisphere 

 is, it is true, overrun by Palsearctic forms, which have extended 

 themselves southwards, in some cases even beyond the isthmus of 

 Tehuantepec. But the great southern mass of the New World has 

 been almost undisturbed by these northern invaders, and in every 

 branch of Zoology — particularly among the Mammals — presents us 

 with such a number of peculiar types, as to render the South 

 American or Neotropical Eegion, after Australia, the most distinct 

 of any of the great Zoological divisions of the world's surface. 



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