Hudsonaster wardi, n. sp., an asteroid, is described from the Ludlowville member of the Mahantango formation near Milford, Pennsylvania. This genus has hitherto been known only from the Ordo- vician. The starfish exhibits such "primitive" characteristics as few, heavy, nonstellate plates around the disc, and has no accessory ossicles in the arms or disc. However, this starfish possesses such "advanced" characteristics as having the superomarginal plates almost completely overlap the inferomarginal plates from the apical side. This feature was predicted by Schuchert to be found in post-Ordovician members of the family Hudsonasteridae. The associated abundant fauna is widespread over the area, and a warm marine environment is sug- gested. "Storm rollers" indicate that the shallow water was occasionally agitated by strong waves.
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