 Over twenty skulls have been found from this dinosaur . As with other lambeosaurines , the animal bore a tall , elaborate bony crest atop its skull , which contained the <unk> narial passages . The narial passages extended into the crest , first into separate pockets in the sides , then into a single central chamber and onward into the respiratory system . The skull of the type specimen has no dermal impressions on it . During preservation it was compressed laterally , so now the width is about two @-@ thirds what it would have been in real life . According to Brown , the compression also caused the nasals to shift where they pressed down on the premaxillaries . Because they were pressed on the premaxillaries , the nasals would have closed the nares . Apart from the compression , the skull appears to be normal . Contrary to what Brown assumed , the areas concerned were fully part of the praemaxillae . 
