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Webster 1913 Edition
Eurypteroidea
‖
Eu-rypˊte-roi′de-a
,Noun.
pl.
[NL. See
Eurypteroid
.] (Paleont.)
An extinct order of Merostomata, of which the genus Eurypterus is the type. They are found only in Paleozoic rocks.
[Written also
Eurypterida
.]