510 0. C. Marsh— New Odontornilhes. 



support of a rudimentary spur. The teeth and the vertebrae in 

 this genus resemble closely those of Hesperornis. 



The present species is based upon the greater part of a skel- 

 eton, including portions of the skull. These remains indicate 

 a huge swimming bird, fully six feet in length, from the apex 

 of the bill to the end of the toes, or somewhat larger than Hes- 

 perornis regalis. The femur and the tibia resemble those in 

 some modern diving birds, but the toes are shorter and stouter. 

 The large rugosity on the metatarsal bone is a striking charac- 

 ter, which may possibly b*^ an indication of sex. The sutures 

 uniting the three metatarsals are well marked. 



The principal dimensions of this specimen are as follows : 



Length of sternum, 



Width in front, 162- 



Extent of five articulations for ribs, 



Length of femur, 



Transverse diameter of distal end, 



Transverse diameter of tibia at distal end, 



Length of tarso-metatarsal, . . - 



Transverse diameter of proximal end, 



Transverse diameter through protuberance, - - - 



Length of first phalanx of fourth toe, 



The known remains of this species are from the Upper Creta- 

 ceous deposits of Western Kansas. 



Hesperomis gracilis^ sp. nov. 

 A second species of Hesperomis, somewhat smaller than H. 

 regalis, and of more slender proportions, is indicated by a few 

 remains in the Yale collection. The most characteristic of 

 these specimens is a left tarso-metatarsal, which in general 

 form is very similar to the corresponding bone in H. regalis, 

 but is much less robust. The following are its principal meas- 



Length (approxi 



Transverse diameter of proximal end, 



Antero-posterior diameter, - 



Distance from proximal end to articulation for hallux,. 

 Transverse diameter of shaft at articulation for hallux, 



Antero-posterior diameter, 



Antero-posterior 'diameter of distal condyle of third 



metatarsal, - - - 



Transverse diameter, 



This species, also, : 

 Kansas. 



Tale College, New Haven, May ] 



