Machairasaurus whole refers to the sabre-like claws of the hand. The holotype, IVPP V15979, was found in layers of the Bayan Mandahu dating from the late Campanian. It mainly consists of a left frontlimb, including the lower end of the lower arm, two carpal bones and a complete hand. Also some fragmentary foot elements were present. The other find is the paratype, IVPP V15980, consisting of a very fragmentary skeleton including tail vertebrae, chevrons, ribs, phalanges of the hands, fragments of the second and fourth metatarsals and pedal phalanges. Five oviraptorid specimens associated with a nest, the female having been found
Roll the Bones strong vocal melodies at the beginning and base the rest of the tune around it. Lifeson had wanted to try playing funk rhythms and attempted it "Presto" and wished to explore it further on "Roll the Bones". The majority of the arrangements worked out at the writing stage remained unchanged which allowed the group to use the demos as a guide for recording, done by transferring the completed demos to 24-track and re-recording the parts. The album contains a running lyrical theme concerning the element of chance in different aspects of life, which Peart had devised while experimenting with lyrics.