On the Sivatherium giganteum. 277 



of the tension of elastic menibranes in modulating the tones 

 produced by them has been very satisfactorily demonstrated 

 by the interesting experiments of Savart*, and it is no doubt 

 materially concerned in the analogous phoenomena of the 

 voice. The diameter of a lube does not influence the pitch of 

 its sound, but there is an obvious appropriateness in the di- 

 minution of the diameter of the trachea as the sound becomes 

 sharper ; for experience has taught the makers of wind instru- 

 ments that the best qualities of tone for the lower notes are 

 obtained when the bore of the instrument is large, and for the 

 higher notes when it is small. 



The influence of the vocal tube, as far as relates to its ef- 

 fects on the key of the voice, is terminated at the velum palati 

 by the several perforations of the nostrils, the Eustachian tubes, 

 and the mouth. The opinion of Savart, that the mouth mo- 

 difies the key of the tone is consequently erroneous f . 



We find analogous acoustic effects in musical instruments ; 

 for instance, the lowest joint of the flute, which is six inches 

 in length, having three perforations, when its keys are open 

 lowers the tone of the instrument only half a note. The im- 

 portant distinction between the effects of air passing through 

 the tubes of musical instruments, according as their sides are 

 rigid or membranous, is, that in the former case, as exemplified 

 in flutes, hautboys, &c., the air vibrates independently of the 

 sides of the tube, whilst in the latter, the tube enters into com- 

 pound vibrations with the column of air. 

 [To be continued.] 



LVII. On the Sivatherium giganteum, a new Fossil Ruminant 

 Genus, from the Valley of the Markanda, in the Sivdlik branch 

 of the Sub-Himalaijan Moimtaiiis. By Hugh Falconer, 

 M.D., Superintendent Botanical Garde?!, Sehdrajipur, and 

 Captain P. T. Cautley, Superintendent Docib Canal. 

 [Continued from p. 201, and concluded.] 



NOTWITHSTANDING the singularly perfect condition of the head, 

 for an organic remain of such enormous size, we cannot but regret 

 the mutilation at the muzzle and vertex, as it throws a doubt upon some 

 very interesting points of structure in the Sivatherium: 1st, the presence 

 or absence of incisive and canine teeth in the upper jaw, and their num- 

 ber and character if present; 2nd, the number and extent of the bones 

 which enter into the basis of the external nostrils; and 3rd, the presence 

 or absence of two horns on the vertex, besides the two intra-orbital 

 ones. 



* Annates de Chimie. 



t Tandis que la bouche en s'ouvrant phis on moins, eten changeant par 

 consequence Ics dimensions de la colonne d'air, exerce aussi une influence 

 notable sur le nombre des vibrations, conjointement avec Ics Icvres.— .^««. 

 de Chimie, 1825. 



