The nema and virgula are shown to be different structures. Fossil Fluid and Rock Processes Laboratory Cluster, Rock Volume Characterisation Laboratory Cluster, Integrated resource management in Eastern Africa, Donations and loans of materials collections. Diplograptus, genus of graptolites, small, extinct colonial marine animals thought to be related to the primitive chordates and restricted to ancient marine environments. Scandant means? Graptolites are an extinct group of entirely marine, colonial organisms that are abundant and very important in the fossil record. 18 of 18. Different Scandant means? Keep up to date with all the latest research, products and events news. MODE OF LIFE OF GRAPTOLITES 537 ' In colonies living in suspension with the sicular aperture facing upwards, a change in the inclination of the stipes to horizontal and