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Webster 1913 Edition


Proostracum


Pro-ös′tra-cum

,
Noun.
;
pl.
Proostraca
(#)
.
[NL., fr. Gr. [GREEK] before + [GREEK] shell of a testacean.]
(Zool.)
The anterior prolongation of the guard of the phragmocone of belemnites and allied fossil cephalopods, whether horny or calcareous. See Illust. of
Phragmocone
.

Definition 2024


proostracum

proostracum

English

Noun

proostracum (plural proostraca)

  1. (zoology) The anterior prolongation of the guard of the phragmocone of belemnites and allied fossil cephalopods, whether horny or calcareous.