单词：graptolites
(graptolite 的复数) n.[古生]笔石( 古元脊椎动物, 现存化石 )
plural of graptolite
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.
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.