Geological specimen - GRAPTOLITE COLLECTION: DIPLOGRAPTUS (GLYTOGRAPTUS) Physical description Diplograptus (Glytograptus) austrodentatus H. and R. Middle Ordovician. Grey rock, multiple graptolite specimens on surface. "Mo51' and 'Mo52' on stickers. Fossil collection was formerly held by the School of Mines Museum, Pall Mall, Bendigo.