THE OTTAWA NATURALIST -" 



Vol. XXVII MAY, 1913 No. 2 



THE MANUS IN A SPECIMEN OF TRACHODON FROM 

 THE EDMONTON FORMATION OF ALBERTA. * 



By Lawrence M. Lambe, F.G.S., F.R.S.C, Vertebrate 

 Palaeontologist, Geological Survey, Ottawa, Canada. 



The present paper has particular reference to the osteology 

 of the front feet, or hands, of a specimen of Trachodon discovered 

 last summer in the Edmonton formation (upper Cretaceous) of 

 Red Deer river, Alberta, by the Geological Survey vertebrate 

 palseontological field party under Charles H. Sternberg. This 

 specimen is now being mounted in high relief preparatory to 

 being placed on exhibition in the museum of the Geological 

 Survey, Ottawa. 



The skeleton of this Trachodon is almost complete from the 

 front margin of the snout to the sixth caudal vertebra, but the 

 remainder of the tail is missing. This defect, however, can be 

 remedied to a great extent in mounting the specimen as 

 fortunately a large portion of the tail of another individual of 

 similar size was found at the same locality and can be used to 

 take the place of the missing vertebras. 4 



This skeleton was found on its right side with the head bent 

 downward, the front legs stretched out, and the long hind 

 legs drawn up. Although it has been subjected to considerable 

 pressure, the effect of which is apparent, there has been remark- 

 ably little displacement of any of the bones. The specimen is 

 being mounted in the exact position in which it was discovered. 

 The rock is a sandy clay, mostly soft and easily cut away, but a 

 tenacious layer of clay iron-stone coats some parts of the skeleton 

 and is removed with difficulty. The bones have undergone a 

 varying amount of silicification and are in parts considerably 

 fractured. 



A clear and sharp impression of the tuberculated skin is 

 preserved to the left of the mid-line of the back, above the sacrum , 

 for a distance of about four feet. Large polygonal tubercles, 



* Communicated with the permission of the Director of the Geological 

 Survey. 



