Y20 William Patten 



which are able to distinguish between the different kinds, 

 it would be absurd to suppose tbat a Coelenterate, with its simple 

 Organization, could make a similar use of such an organ. 



Surely, then, these otolithic sacs cannot function as auditory organs, 

 in the ordinary sense of the terni ; but that they are homologous with 

 them, orhavean analogous function, i. e. the reception of vibrations, 

 is beyoud doubt. We are therefore compelled to assume that they, like 

 the eyes , are structures which bave , or may bave, two different func- 

 tions ; that construction most advantageous for the performance of the 

 first beiug likewise most favorable for the performance of the second. 

 When the structure of the organ reached this condition, equally favor- 

 able for the performance of either function , then the transfer of func- 

 tion took place. 



The difficulty of accounting for these organs according to the 

 generally accepted, or prevalent views has led me to explain their 

 existence by supposing that they are not organs by which the animai 

 becomes cognizant of certain vibrations, but organs for the recep- 

 tion, and for the conversion, of these vibrations into nerve 

 Stimuli. Upon these Stimuli, together with those received by other 

 organs, depends the entire activity of the animai. There is no such 

 thing as voluntary muscular contraction in these simple organisms. 

 Ali the contractions depend upon Stimuli received from 

 without, and which are carried by the nerves to the con- 

 tractile organs; however slight these irritations are, stili 

 they are forms of energy and just the energy, or force, 

 necessary to liberate that potential energy contained in 

 complex protoplasmic Compounds, in the shape of motion. 

 The Stimuli may also be used for the concentration of the energy 

 contained in comparatively large quantities of matter into a much 

 smaller volume. Additional Stimuli liberate the energy as motion. It 

 is very probable that ali sense hair cells convert the energy of move- 

 ment, or coarser vibrations, into nervous Stimuli. 



The amount of work done by these Stimuli depends upon the 

 amount lost in receiving and transmitting them, or, in other words, upon 

 the delicacy of the scuse cells and nerve fibres. Therefore the isolated 

 and unprotected sense cells teud to accumulate in groups, sheltered in 

 pits or sacs. Accessory bodies in favorable positions, as otoliths, are 

 added to incorporate the vibrations, so to speak. Now a Medusa may 

 possess an otolithic sac capable of recording to perfection the fìner 

 vibrations, and Converting them into corresponding nerve sensations ; 



