358 AVERS. 



EXPLANATION OF PLATE XL 



Fig. I. A part of a vertical section of the crista acustica of the Cat's ear. X 1400. 

 To show the effect of reagents on the hairs, and the course of the nerves and the 

 blood-vessels. The very large cupula terminalis is not drawn in. g.s., varicosity of 

 nerve fibre, n. b.v. and b.c, blood-vessel and contained corpuscles, m.c, mucous 

 cell, m., mucus exuded therefrom, h., h. 1, h. ^, various forms of hair cells, — rem- 

 nants. e/>., non-sensory epithelium. 



Fig. 2. A vertical section of the membrana tectoria, or hair band, of the Virginia 

 Opossum. X 895. o.h.e.c, cell cap of outer hair cell, with its hairs rising into the 

 mass of the band. The entire absence of a " Rand Korper " is noteworthy, c.p., 

 Corti's pillars, o.h.c, body of outer hair cells, not drawn in detail. 



Fig. 3. A bundle of lagenar hairs of the Alligator, to show the relation of the 

 otoliths to the hairs. Hrtnk., ob. 8, oc. 2. Methyl blue. 



Fig. 4. A cap of a hair cell from the cochlear organ of the Alligator. X 1400. 



