90 A. M. Mayer—Researches in Acoustics. 
to Helmholtz that these were suitable bodies to effect the 
ducted alate to the discoveries contained in his renowned 
work, “Die Lehre von den Tonem Radangen.. * In this 
poral bone, is necessarily difficult to dissect, and even when a 
view is obtained of the o rgan of Corti, its parts are rarely im situ ; 
and, moreover, they have already had their natural structure 
altered by the acid with which the bone has been saturated to 
render it soft enough for dissection and for the cutting of 
sections for the microscope. 
s we descend in the scale of seep ey, from the higher 
vertebrates, we observe the parts of the outer and middle ear 
disappearing, while at the same time we see the inner ear 
gradually seins toward the surface of the head. T 
external ear, the auditory canal, the tympanic membrane, and 
with the ioe the now useless ossicles, have disappeared in the 
a. —— and there remains but a rudimentary 
receives the pees Merete will be more ex than in 
higher organisms. Indee very minuteness of the crear 
art of the articulates ae fdicate this, for a tympanic mem- 
rane placed in vibratory communication with a modi 
theory, but the leading-thread of theory, and th + sporent ‘of aa 
means of observation, have facilitated it in an Saceere e 
“ Above all things I beg the reader to remark that the hypothesis on the co- 
vibration of the organs of Corti has no immediate Scots with the explanation of 
consonance and which rests solely on the facts of penn 1% on the 
beats of harmonics and of resultant sounds.”—Helmholtz, Tonempfindungen, 
Ps Acoraing Waldeyer, there are 6,500 inner and 4,500 outer pillars in the 
