3 
If correct in these deductions a comparison of the digits of Dromceo- 
saurus and Geological Survey specimen No. 2367, so far as they are compar- 
able, appears at once sufficient to show that they pertain to feet that are 
structurally very unlike. This conclusion appears to be substantiated by 
the Coelurid aspect of the foot of specimen No. 2367 and also by the 
presence in the Belly River formation of dentaries totally distinct from 
those of Dromceosaurus, and which in the slenderness of their proportions 
appear to have affinity with the slender elongated feet of the present 
specimen, with which they are, therefore, provisionally associated. 
In view of the above evidence the name Chirostenotes pergracilis is 
proposed for this specimen. The species name is from Mr. Lambe’s notes 
and I take great pleasure in using it. 
The remote possibility of this species falling within the genus Coelo- 
saurus, of Leidy, from the Cretaceous greensands of New Jersey, is, of 
course, recognized, but unfortunately at this time the lack of homologous 
skeletal parts prevents direct comparison from being made. The close 
resemblance, except in the much smaller size, of the type ungual of Coelurus 
gracilis Marsh, from the Arundel formation of Maryland, to unguals from 
the Belly River formation that may now be correlated with Chirostenotes 
pergracilis, has been fully pointed out 1 . Matthew 2 has referred Coelurus 
gracilis with doubt to the genus Dromceosaurus. In view of the very great 
similarity of the type to the unguals of Chirostenotes pergracilis it should 
now be removed to this genus. The possibility of the present specimens 
being cospecific with some of the named forms from the Judith River 
formation of Montana, as Deinodon cristatus (Cope), or Deinodon Icevifrons 
(Cope), is also recognized, but the totally inadequate nature of the type 
materials, consisting of single teeth, on which these names were based, 
makes it very improbable that other specimens can ever be certainly 
identified with them. 
Description of a New Carnivorous Dinosaur Chirostenotes Pergracilis, 
New Species 
PLATE I 
Type: No. 2367, Geol. Surv., Can., consists of the nearly complete 
articulated digits of both fore feet. Collected by G. F. Sternberg, 1914. 
Locality: Sec. 17, tp. 21, range 11, W. 4th mer., 2 miles due northeast 
of the mouth of Little Sandhill creek, Red Deer river, Alberta. 
Horizon: Belly River formation, Upper Cretaceous. 
The specimen selected as the type of the present species consists of 
the greater part of the articulated bones of both hands, shown as found 
in situ in Plate I. Unfortunately neither manus is complete, but from 
both it has been possible to reconstruct most of the digital structure, as 
may be seen in Figure 1. 
i Gilmore, C. W., Proc. U.S. Nat. Mus., vol. 59, 1921, pp. 585-586, Pi. 110, Figs. 4, 5. 
* Op. cit., p. 376. 
