2. _Sub-Genus_--ACASTA, _Leach_. (Darwin, 'Balanidæ,' p. 302.)
Valvæ testæ 6; parietes et basis non porosa; basis calcarea,
cyathiformis, non elongata. Spongiis, aut rarò Isidis cortici, affixa.
A Monograph on the Sub-class Cirripedia (Volume 2 of 2) The Balanidæ, (or Sessile Cirripedes); the Verrucidæ, etc., etc. · 第 188 / 417 题