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Webster 1913 Edition
Paleechinoidea
‖
Paˊle-ëchˊi-noi′de-a
,Noun.
 pl.
 [NL. See 
Paleo-
, and Echinoidea
.] (Zool.) 
An extinct order of sea urchins found in the Paleozoic rocks. They had more than twenty vertical rows of plates. Called also 
Palaeechini
. [Written also 
Palaeechinoidea
.]