radular tooth formula = ∞. 14. 27. 1. 27. 14. ∞

http://en.wikipedia.org/wiki/Radula

Each row of radula teeth consists of

• one central tooth (or rachis tooth)
  
• on each side : one or more lateral teeth
  
• and then : one or more marginal teeth.

This arrangement of the teeth is expressed in a teeth formula, with the following abbreviations :

• R : designates the central tooth or the rachis tooth (in case of lack of central tooth : the zero sign 0)
  
• the lateral teeth on each side are expressed by a specific number or D, in case the outer lateral tooth is dominant.
  
• the marginal teeth are designated by a specific number or, in case they are in a very large numbers, the infinity symbol ∞

This can be expressed in a typical formula such as:

3 + D + 2 + R + 2 + D + 3

meaning : on each side 3 marginal teeth, 1 dominant lateral tooth, 2 lateral teeth and one central tooth.

This results in 7 basic types :
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