508 0. C. Marsh— New sub-order of Pterosauria. 



There are four phalanges in the wing finger, and the metacarpal 

 that supports it is longer than one half the ante-brachium. In 

 one specimen, which probably belongs to this genus, there are 

 four slender bones, apparently all metacarpals, which are 

 pointed above, and do not reach the carpus. Another speci- 

 men, which is described below, and probably belongs to this 

 genus, has five vertebrae in the sacrum. 



The nearl}-- complete skull mentioned above maybe regarded 

 as the type of the genus Pteranodon. Its principal measure- 

 ments are as follows : 

 Length from occipital crest to end of premaxillary about 



Transverse diameter of occipital condyle, 8'4 



Distance from occipital condyle to distal end of quadrate, 105- 



Length of lower jaw about 23 inches, or 584- 



Greatest depth, 62-2 



Depth at articulation for quadrate, 23-2 



The species represented by this specimen is well marked. 

 and may be called Pteranodon hngiceps. It is somewhat larger 

 than P. occidentalis Marsh, which apparently has more slender 

 jaws. The Yale collection contains portions of a skull indicating 

 a much larger species, which is probably P. ingens Marsh. It 

 this skull was of the same proportions as that just described, 

 its length would be no less than four feet ! 



One of the smallest American species yet found is represented 

 in the Yale Museum by several bones of the wing, a number of 

 vertebrae, and the nearly complete pelvis. The wing-bones 

 preserved are elongated, and very slender. The pelvis is un- 

 usuallv small, and there are five vetebrse in the sacrum. The 

 last of the series indicates that the tail was short. The follow- 

 ing are the principal dimensions of this specimen : 



Length of ulna, 187* """" 



Length of metacarpal of wing finger, 300- 



Antero-posterior diameter of outer condyle at distal end,. 15- 



Transverse diameter of shaft, above condyles, 13. 



Length of first phalanx of wing finger, 347. 



Extent of five vertebi-ae of sacrum, 57. 



This species, which may be called Pteranodon gracilis, was 

 about two-thirds the size of P. velox Marsh. It probably meas- 

 ured about ten feet between the tips of the expanded wings. 



All the specimens here mentioned are from the Upper Cre- 

 taceous of Western Kansas. It is an interesting fact that the 

 localities and geological horizon of these specialized, toothless, 

 Pterodactyles are precisely the same as those of the Odont-^ 

 omiihes, or birds with teeth, and the two doubtless lived 

 together in the same region. 



Tale CoUege, New Haven, May 15, 1876. 



