TONGUE AND GUSTATORY OEGANS OF MEPHITIS MBPHIT10A. 167 



EXPLANATION OF PLATE XI, 



Illustrating Mr. Frederick Tuckerman's paper on " The Tongue 

 and Gustatory Organs of Mephitis mephitica." 



Fig. 1. — Vertical section through the right circumvallate papilla. S. P. 

 Secondary papillae, t. The trench. r. Section through the ridge which 

 surrounds the trench, t. b. The taste-bulbs arranged in tiers, gl. d. The 

 ducts of the serous glands, opening into the bottom of the trench, m. m. 

 Mucous membrane. ( x 20 times.) 



Fig. 2. — Vertical section through the same circumvallate papilla. S. P. 

 Secondary papillae, t. The trench, r. Ridge. C. P. Conical papilla, some- 

 what depressed, t'. The trench passing beneath the papilla, showing the 

 arrangement of the taste-bulbs in the epithelium of the under surface, gl.d. 

 The ducts of the serous glands. ( X 24 times.) 



Fig. 3. — Vertical section through the posterior part of the same papilla. 

 t. The trench, t. b'. Taste-bulbs in the epithelium of the upper surface. 

 m. t. The mid-trench, partly separating the papilla into two divisions, gl. d 

 Ducts of the serous glands, (x 20 times.) 



Fig. 4. — Vertical section through the anterior part of the same papilla. 

 t. b. Taste-bulbs, divided at right angles to their long axis. gl. d. Ducts of 

 the serous glands. ( X 30 times.) 



Fig. 5. — Vertical section through the base of the same papilla, showing 

 the bottom of the trench and the six lowest tiers of taste-bulbs, t. The 

 trench, t. b. Taste-bulb. g. p. Gustatory pore. s. e. Stratified epithelium. 

 o. I. Outer layer of stratified epithelium, gl. d. The ducts of the serous 

 glands, m. m. Mucous membrane. ( x 240 times.) 



Fig. 6. — Vertical section through a fungiform papilla, from the group in 

 front of the circumvallate papillae, t. b. Taste-bulbs, p. p. Papillary pro- 

 cesses, s. e. Stratified epithelium. ( x 220 times.) 



Fig. 7. — Transverse vertical section through the upper part of the posterior 

 surface of the epiglottis, f. s. Free surface of the stratified pavement of 

 epithelium, d. I. Deep layer of columnar cells of the epithelium, b. I. s. 

 Bulb-like structure lying in the mucosa, with its apex touching the base of 

 the cells of the deep layer of epithelium, m. m. Mucous membrane. ( x 240 

 times.) 



