LATE PALEOZOIC TURRILEPADID MACHAERIDIANS FROM NORTH-AMERICA

Turrilepadids are not uncommon in late Paleozoic shales being often as sociated with ostracodes, foraminifers, and minute molluscs, In North America they range from the late Missippian (Chesterian) to early Perm ian (Leonardian). Sclerites of the inner scleritome row are more commo n than outer sclerites. Some clusters have been found. Sclerite consis ts of two layers with the thicker, lower layer penetrated by a transve rse tubular structures oriented perpendicular to the sclerite surface, which may represent canals related to the papillae on the inner surfa ce of the sclerite. Turrilepas lepros sp. n., T. trigoniodes sp. n., T . asketos sp. n., Clarkeolepis alloeospinosa sp. n., and Ambonlepidos petalos gen. et sp. n. are proposed.