Eaton — John Day Felichc in Marsh Collection. 441 



Similarly the interorbital breadth of the present species 

 exceeds the corresponding measurements in Nimravus, 



Dinictis, and Pogonodon, as may be seen from the com- 

 parison of the interorbital indices, computed from the 

 interorbital diameter and the basal length. The inter- 

 orbital breadth index of Dincelurus crassus is 35 while 

 that of the other well-known speices is as follows : Nimra- 

 vus gomphodus 25 (approx.) ;. N. debilis 26; N. d chilis 



Fig. 6. 



Fig. 6. — Dincslurus crassus, gen. et sp. nov. Holotype. X %• 



major 24; Pogonodon davisi 28 (approx.) ; P. platycopis 

 27 (approx.) ; P. semdidens 28 (approx.) ; Dinictis 

 cyclops 33; D. sqiialidens, No. 8777, A. M. N. EL, 28; 

 D. fortis 33 (from illustration). 



The diameter of the postorbital processes of the frontal, 

 which here gives an index of 46 when contrasted with the 

 basal length, is relatively mnch greater than in Nimravus 

 where the range is from 34 to 36. In Pogonodon this 

 index has a wider range, as the following values show: 



Am. Jour. Sci — Fifth Series, Vcl. IV, No. 24. — December, 19C2. 

 29 



