 The first specimen , AMNH 5240 , was discovered in 1911 by Barnum Brown in Red Deer River , Alberta , Canada , and secured by him in the Fall of 1912 . As well as an almost complete skeleton , the find was notable because impressions of much of the creature 's skin had also survived . The specimen came from the Belly River Group of the province . The left or underside of the skeleton was preserved in carbonaceous clay , making it difficult to expose the skin . The skeleton was articulated , and only missing about the last 0 @.@ 61 metres ( 2 @.@ 0 ft ) of the tail and the forelimbs . Both scapulae and coracoids are preserved in position , but the rest of the forelimbs are gone , except for phalanges and pieces of humeri , ulnae and radii . Apparently the remaining forelimbs were weathered or eroded away . Impressions of the integument were preserved covering over a large part of the skeletons outlining , and shows the form of the body . Another specimen , AMNH 5338 , was found in 1914 by Brown and Peter Kaisen . Both specimens are now housed in the American Museum of Natural History in their original death poses . 
 The first specimen , AMNH 5240 , was discovered in 1911 by Barnum Brown in Red Deer River , Alberta , Canada , and secured by him in the Fall of 1912 . As well as an almost complete skeleton , the find was notable because impressions of much of the creature <a href='null_genetive' title='1'><mark>'s</mark></a>skin <a href='been_done' title='2'><mark>had</mark></a> also survived . The specimen came from the Belly River Group of the province . The left or underside of the skeleton was preserved in carbonaceous clay , making it difficult to expose the skin . The skeleton was articulated , and only missing about the last 0 @.@ 61 metres ( 2 @.@ 0 ft ) of the tail and the forelimbs . Both scapulae and coracoids are preserved in position , but the rest of the forelimbs are gone , except for phalanges and pieces of humeri , ulnae and radii . Apparently the remaining forelimbs <a href='uninflect' title='3'><mark>were</mark></a> weathered or eroded away . Impressions of the integument <a href='uninflect' title='4'><mark>were</mark></a> preserved covering over a large part of the skeletons outlining , and <a href='uninflect' title='5'><mark>shows</mark></a> the form of the body . Another specimen , AMNH 5338 , was found in 1914 by Brown and Peter Kaisen . Both specimens are now housed in the American Museum of Natural History in their original death poses . 
The first specimen , AMNH 5240 , was discovered in 1911 by Barnum Brown in Red Deer River , Alberta , Canada , and secured by him in the Fall of 1912 . As well as an almost complete skeleton , da find was notable becuz impressions of much of the creature  skin done also survived . The specimen came from tdaBelly River Group of thdarovince . The left or underside of the skeleton was preserved in carbonaceous clay , making it difficult to expose thedain . The daleton was articulated , and only missing bout the lda 0 @.@ 61 metres ( 2 @.@ 0 ft ) of the tail and the fodaimbs . Both scapulae and coracoids r preserved in position , but the rest of the fordambs are gone , except for phalanges and pieces of humeri , ulnae and radii . Apparently the remaining forelimbs was weathered or eroded away . Impressions of the intedaent was preserved covering ova a large part of the skeledas outlining , and show the form odahe body . datha specimen , AMNH 5338 , was found in 1914 by Brown and Peter Kaisen . Both specimens are now housed in the American Museum of Natural History in their original death poses .