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'^■LIBRARY 



THE OTTAWA f(ATURALIST. 



Vol. XVIII. OTTAWA, MAY, 1904. No. 2 



THE GRASPING POWER OF THE MANUS OF 

 ORNITHOiMIMUS ALTQS,* LAMBE. 



By Lawrence M. Lambe, F.G.S., F.R.S.C, of the 



Geological Survey of Canada. 



(With two plates.) 



In the collection of vertebrate remains from the Belly River 

 series of the Cretaceous of Alberta, Canada, made by the writer 

 in igoi, there are a number of phalanges of the manus of Oriiith- 

 oniinius alius that throw further light on the structure of this 

 dinosaur and on its probable habits. As little is known of the 

 manus, or indeed of the skeleton generally of the different species 

 of this genus, it is thought that a few descriptive remarks on the 

 phalanges of the Belly River form may prove of some interest. 



Of the pes of O. altus we already know that it was adapted 

 to swift running and that the digits terminated in long, rather 

 straight, pointed claws. 



Five species of the genus have been named by Marsh from 

 the Upper Cretaceous of the Western States. These are : O. velox 

 from the " Ceratops beds of Colorado," O. tenuis and O. grandis 

 from the " same horizon in Montana," and O. sedens and O. 

 mimitiis from the "Ceratops beds of Wyoming." Of these species 

 scarcely anything is known of the fore limb. Marsh describes 

 and figures the metacarpals of O. velox and a claw bone of the 

 manus of O. sedetis. 



The material collected by the writer does not admit of the 

 reconstruction of the entire manus. It proves that the claws were 

 of quite a different shape from those of O. sedens. (Fig 9.) 



* Communicated by permission ot the Acting- Director of the Geological 

 Survey of Canada. , 



