Graptolite

[græptәlait]

Definition

(n.) One of numerous species of slender and delicate fossils, of the genus Graptolites and allied genera, found in the Silurian rocks. They belong to an extinct group (Graptolithina) supposed to be hydroids.

Editor: Lois

Definition

n. one of a group of fossil hydrozoa having simple or branched polyparies usually strengthened by a horny-like rod—the 'solid axis.'

Editor: Vlad