INNERVATION OF INTEGUMENT OF CHIROPTERA 317 



with nerves and are perceptive. (2) The affirmation of Schobl 

 that into each hair folhcle there enters one nerve is not true. 

 Each hair is supphed with many nerve fibers, five to six or more, 

 which approach the folhcle, together or separately, and from 

 different sides. They may unite into two or three small trunks. 

 On reaching the neck of the hair the nerves divide, lose their 

 medullation, and are distributed on the hyaline membrane more 

 or less like radiations, ending freely at about the same level. 

 (3) The nerve ring of Schobl does not exist, neither do the 'Ter- 

 minalkorperchen.' (4) At the level of the superficial subepithelial 

 network of nerves, minute threads are seen which surround the 

 follicle and disappear in the epithelial sheath. 



Arnstein ('76) recognized two different kinds of nerve termi- 

 nations on hairs: (1) The free endings on the hyaline membrane 

 in the form of a 'palisade;' (2) The nerve network which occurs 

 in the outer root sheath. 



Bonnet ('78), who investigated the innervation of the hair 

 follicles of a number of mammals including the bat, confirmed 

 Arnstein's observations on the endings of nerves on the hyaline 

 membrane. Bonnet's idea was that a nerve ring exists in con- 

 nection with each hair. The small fibers which constitute this 

 structure lie outside of the straight fibers, which terminate in a 

 'palisade,' and surround them much as hoops surround a barrel, 

 in the form of a ring consisting of six or more pale fibers. Of the 

 root sheaths in the region of the sebaceous glands Bonnet says, 

 "This is a rendezvous of the various small medullated nerve 

 fibers which come to the hair partly above and partly below the 

 sebaceous glands. These fibers going to the follicle spread out 

 forming a woven net of minute medullated fibers." 



In describing the innervation of the hair of certain mammals, 

 including bats, Szymonowicz ('01) pointed out that the medul- 

 lated fibers approach the follicle below the sebaceous glands, 

 divide, losing their medullation, and penetrate to the hyaline 

 membrane, where some of the fibrils encircle the hair, while others 

 end on the hyaline membrane. The latter fibrils branch regu- 

 larly, and run parallel with the long axis of the hair. This 

 investigator observed perceptive menisci in a strongly developed 



JOURNAL OF MORPHOLOGY, VOL. 25, NO. 2 



