90 Transactions of the 



ceeded in office as First Commissioner by Mr. Adam, who has 

 kindly intimated his willingness to reconsider the question of the 

 much-desired accommodation of this Society in juxtaposition with 

 other kindred societies ; and it is sincerely to be hoped that his suc- 

 cessor in office may not be less favourable than himself to the 

 aspirations of this Society respecting accommodation in Burhngton 

 House. 



The principal features of the papers published in the Trans- 

 actions of this Society during the past year have been noticed in 

 the Keport; but there are some to which special attention may 

 perhaps with advantage be directed. Among them may be men- 

 tioned a paper " On the Structure and Function of the Eods of the 

 Cochlea in Man and other Mammals," by Dr. Urban Pritchard ; 

 this paper did not seem to attract the amount of attention it 

 deserved, affording as it does a clue to the mechanism by which 

 one of the most important functions of the ear is fulfilled ; it per- 

 haps, therefore, may not be undesirable to make a few observations 

 upon this subject. The internal ear consists of two important parts, 

 namely, the semicircular canals, and the cochlea, cavities imbedded 

 in the densest bone in the body. The semicircular canals consist of 

 three tubes of a form nearly approaching to that which their name 

 implies, and these are placed with respect to each other in a very 

 remarkable position ; in all classes of animals they lie in three planes 

 perpendicular to each other, so that each is placed at right angles 

 to the other two. They are found in all classes of animals, from 

 the highest down to the cartilaginous fishes, and they occupy the 

 same position in all. Their chief function is undoubtedly to deter- 

 mine the direction of sound : valid reasons have long since been 

 assigned by the writer for assuming this to be the case. 



The other important organ is the cochlea. This may be de- 

 scribed as a conical tube spirally convoluted upon itself, resembling 

 an ordinary snail-shell, and supposing it placed with the axis of the 

 whorl vertical, it is divided horizontally into two portions by a thin 

 plate, partly of bone and partly membrane, running through its 

 whole length from the larger to the smaller end, the membranous 

 portion consisting chiefly of a great number of transverse fibres. 

 On these rest the outer ends of the " rods of the cochlea," or the 

 " rods of Corti," the inner extremities of which rest on the bony 

 portion of the spiral lamina. These rods consist of two portions 

 jointed together, which form a kind of arch, much resembling the 

 widely-extended finger and thumb. It is stated in the paper that 

 the number of the inner and outer rods is not alike, three of the 

 inner corresponding with two of the outer, thus . ' . " . ; but it 

 appears more probable that their arrangement is alternate through- 

 out, thus .■.•.•.•.'.•.•."., and not thus . • . ' . . * . ' . .'.'., 

 each of the outer rods being in fact articulated between two of the 



