moderately, is but Utile developed. For tlie lower liiDhs it imist be 

 already higlier, because the movements wliicli tliey perforui are already 

 much more complicated. 



In yet higher degree this is the case with our arms. So it is 

 known, that as soon as our e(|uilibrium gets in any danger, we do 

 not only immediately put oui- arms into function, but that we trust 

 even more to our arms, which are weaiver concerning our muscle 

 strength than to our much more muscular legs. If the equilibrium 

 sensation of our arms has already reached a high degree, this will 

 be yet more so with our head, which is al)ove all designed to bring 

 to our knowledge oui- attitude in s[)ace. It speaks for itself that 

 without this knowledge no eciuilibrium is possible. Moreover, with 

 exception of the lower jaw, the different parts of the head are not 

 liidced together by joints, but they are tightly grown together. That 

 this puts the head into an extraordinary relation is comprehensible. The 

 trunk and the limbs are in opposition to the head composed of 

 movable parts, which are joined together by tendons and sinews. 

 All the changes in attitude, therefore also those which are of 

 importance for our equilibrium, come to our consciousness. This is 

 not the case with our head. 



By means of the neck and all that is connected with it, it can, 

 however, fix its own podure with relation to our body, but it will 

 not be of any use for the determination of the e(iuilibrium. 



The equilibrium organ of the head has, on account of what was 

 above reported, to be not oidy much more highly developed, but it 

 must be diiferently composed from the equilibrium paths for the trunk 

 and the limbs. Therefore too the vestibular organ is built up in a 

 dift'erent way. As the joints in our head, necessai*y for the eqiiili- 

 brium, are all missing, it is most probable, that the statoliths 

 through movements during the changes of attitude stimulate the 

 equilibrium fibres and thus put into action the necessary afFerent- 

 proprioceptive impulses. The central nervous system is immediately 

 warned of any danger that threatens our eciuilibrium and can take 

 the necessary steps against it. 



CONCLUSIONS. 



a. The sixth equilibrium sense is not placed in the vestibular 

 organ only, but has its tracts spread over the whole body. 



I). The vestibular organ is, as far as it refers to our equilibrium 

 only to be considered as a part of the equilibrium sense. 



c. The different parts of this sense can compensate each other 

 reciprocally. 



