Glossary of Morphological and Anatomical Terms

ear - Flattened or pointed cardinal extremity of shell subtended between hinge line and lateral commissure usually distinct from corpus.Fig.283.
ear baffle - Ridge differentiating ear from corpus in some productides.
echmidium - Spear-shaped plate formed during ontogeny of loop of Paleozoic terebratulides by fusion of anterior ends of descending lamellae.Fig.338.
elytridium - Narrowly convex, puckered cover of delthyrium in aulostegids.
emarginate - Median segment of anterior commissure deflected posteriorly.Fig.288_2a,Fig.288_3a.
emarginatura - Median semicircular opening bisecting apical region of the ventral valve of some oboloids.
endopuncta - Perforation of shell separated from periostracum on external surface by sievelike canopy of primary shell; occupied by caecum as in terebratulides, thecideidines, and spiriferides; also used for perforations ending within the primary layer of some rhynchonellides.Fig.31.
endospines - Fine, solid or hollow, short spines on interior of shell.
ephebic - Mature.
epithyrid - Pedicle opening wholly within ventral umbo and ventral from beak ridges.Fig.318.
equidistribute - Vascula genitalia, vascula myaria, and vascula media all well developed and contributing to mantle canal circulation.Fig.381.
erect spines - Spines projecting at high angle (more than 70°) from shell surface.
erisma - Plate supporting cardinal process and brachiophore of orthotetidines; See socketplates.
exopuncta - Perforation of externalshell surface commonly restricted to primary layerand never penetrating to internal surface.
extremities - See cardinal extremities.
extropuncta - Microscopic, asymmetrical, conical deflection of laminae of secondaryshell invariably pointing externally, characteristic oforthotetidine schuchertellids.Fig.271.