116 



SMELL, TASTE, ALLIED SENSES 



where compound buds with as many as six pores have 

 been identified. The frequency with which types of buds 

 with different numbers of pores occur may be gathered 

 from the enumeration by Heidenhain who found that in 

 509 taste-buds from the foliate papillas of the rabbit 

 368 had one pore, 100 two pores, 29 three pores, 7 four 



Fia. 28. Lateral view of the catfish, Amiurus melas, showing in black the gustatory 

 branches of the facial nerve. After Herrick, 1903, Fig. 3. 



pores, 1 five pores, and 4 six pores. In the compound 

 buds the pores usually form a more or less linear series 

 and as each pore represents a single element in the com- 

 plex the whole gives the impression of a row of fused 

 buds (Fig. 30.) These compound buds are believed to 

 result from a process of imperfect division. 



Some taste-buds open directly on the oral surface 

 where they are located ; others are marked by a pore, the 

 outer taste-pore, which leads into a short canal and this 

 in turn ends at the inner taste-pore formed by the distal 

 end of the bud itself. Von Ebner (1897) noted that in 

 some instances the canal expanded into a small chamber 

 or ampulla over the tip of the bud and, though Graberg 

 (1899) could not confirm this statement for man, the 

 condition has been observed anew by Kallius (1905) in 



