CUTAJSTEOTJS NEEVE-TERMmlTIONS INMAMMALS. 547 



point out the share which the habits of the animal have had iu 

 forming so apparently unique an organ out of elements existing 

 plentifully in every mammal, and show that, in short, it is merely 

 formed by a combination of the invariable intraepithelial nerves 

 of the locality, common to all the Mammalia, with the nerve-endings 

 belonging to the hairs or whiskers. These latter, by the peculiar 

 digging movements of the Moles, have so often been torn out 

 that finally the hairs have become entirely suppressed, although 

 the arrangements of the nerve-terminations upon their follicle 

 remain behind ; and these, modified in appearance by the absence 

 of the hair, now go to form what is known as the " organ of 

 Eimer." 



In the original article in which Eimer * announced his discovery 

 of that organ, he states that if a live Mole be confined in a vessel, 

 it soon shows, by the manner in which it feels all over the walls 

 of its prison with its proboscis, that that structure must possess 

 the sense of touch in a high degree ; and it seems to have been 

 this behaviour on the part of the Mole which induced Eimer to 

 search for and discover its peculiar nerve-apparatus. He also 

 enlarges upon the special anatomical richness of the snout iu such 

 nerve-organs, which he enumerates as amounting to 5000 j and 

 he holds that, physiologically, the sensitiveness is demonstrated 

 by the fact that a smart tap on the nose kills the animal. Let 

 us, however, remark in passing, that if all the hairs were plucked 

 out of any particular part of this animal's or of any other animal's 

 body, and the shrinking together which this would entail in the 

 part operated upon be taken into consideration, the nerve-supply 

 would appear to be equally plentiful with what is seen upon the 

 Mole's proboscis. Thus Eimer has somewhat exaggerated the 

 anatomical importance of the part, iu nerves, just as he has mag- 

 nified its physiological importance, as those who know the extreme 

 sensitiveness of the smaller Shrews to impressions even upon their 

 tails, may easily conceive. It was similar watching of the habits 

 of Eats which led Jobert to look for tactile hairs on the tails of 

 those animals, and to prove to his own satisfaction that the exis- 

 tence of such hairs (8552 in number, according to his enumeration) 

 rendered the tail a tactile organ. He also thought that he settled 

 the matter completely by cutting oif a Eat's tail and finding that 

 thereby its agility was impaired — the fact, however, being that what 



* "Die Schnauze des MaulwurJs als Tastwerkzeug," Archiv fiir luikrosko- 

 pische Anatomic, 1871, vol. vii. p. 181. 



41* 



