(for preparation see under Higher Taxa: Pteropoda, paragraph Techniques).

series of chitinous teeth in the buccal mass used in catching prey and feeding. In the radula of Heteropoda, one median, one lateral and a pair of additional lateral teeth are distinguished so that in all taxa the formula is 2-1-1-1-2; in pteropods the first- or the additional last lateral teeth are sometimes different from the others. The additional (a), lateral (l), modified lateral (ml) and median (m) teeth are given in a radula formula as (a)-l-(ml)-m-(ml)-(l)-(a);
some examples of radula formulas are: Limacina 1-1-1; Cavolinia 1-1-1; Peraclis (1)-1-1-1-(1); Pneumodermopsis 6-1-6; Pneumoderma 1-0-1; Thliptodon 3-(1)-1-(1)-3; Clione 15-1-15.

Alternative forms for radula : radular, radulas.