FIGURE 1 in A review of the Polystira clade—the Neotropic's largest marine gastropod radiation (Neogastropoda: Conoidea: Turridae sensu stricto)

FIGURE 1. Homology of seven primary (or principal) spiral cords (A–G—notation introduced herein) in four morphologically disparate species of Polystira. Penultimate and final whorls of (left to right) two undescribed species, P. coltrorum Petuch and P. tellea (Dall) showing variation in outline shape, strength, spacing and intercalary cord development and, also rostrum length. Not to scale.