134 LLOYD M. BEIDLER 



The number of taste buds varies with the species as is shown for the 

 circumvallate papillae in Table 2. Although the number of available 

 sensory receptors is often associated with the ability to discriminate quality 



Table 1. Chorda tympani of cat. 



From Foley, 1945. 

 Table 2 



: Number Taste 

 Animal buds in 



I circumvallate 



From Tuckerman, 1890-1 



in other sensory systems, this is of less importance in taste. In some cases 

 a human can discriminate sour, salty bitter and sweet, when the sapid sub- 

 stances are limited to but one fungiform papilla containing only a few taste 

 buds (Ohrwall, 1891). The number of activated taste nerves is not known 

 precisely in this case, but can be estimated as between 6 and 12. 



The structure of the taste bud was often described around the turn of the 

 century. Recently the electron microscopists have reinvestigated the taste 

 buds and the most recent findings have been described by de Lorenzo in an 

 earlier chapter of this book. It is important for the electrophysiologist to 

 note that a single axon in the chorda tympani nerve innervates many 

 (possibly 4-8) different taste cells of a single taste bud and that one taste 

 cell may be doubly innervated. Thus the receptor-axon relationship is not 



