PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 69 



deep as in corresponding vertebrae of Stenodelphis and other living 

 porpoises. There is also a longitudinal carina on the concave floor 

 of the neural canal, like on the lumbars of Delphinodon dividv/in. 

 That this lumbar is an anterior one is shown by the width of the 

 neural canal and the anteroposterior diameter of the neural arch 

 at the base. 



If any reliance can be placed upon the proportions of the trans- 

 verse processes, then the caudal also is an anterior one. No impor- 

 tance is attached to the perforation of the transverse process at the 

 base, because in the caudal vertebrae of Phocaena phocoena the fora- 

 men is very variable in its appearance. Skeletons were examined 

 in wliich the second caudal was the first with the transverse proc- 

 esses perforated at the base; on others it was the third, fourth, or 



Figs. 1-2. — 1, Dorsal View of Type Lumbar of Delphinapterus huschen- 

 BERGEEi Cope. 2, Ventral View of Type Caudal of Delphixapterus 



BUSCHBNBBRGERI COPB X %. (AFTER CASE) 



even the fifth, and in one instance it was the seventh. In case of 

 anotiier porpoise, Neomeris phocaenoides, the eighth caudal was the 

 first with the transverse processes perforated at the base. On the 

 fossil caudal there is a depression above the transverse process, but 

 not below. The inferior surface of the centrum is eroded at both 

 ends, which accounts for the absence of the facets for the chevron 

 bones. The transverse processes are relatively very narrow. 



For their position in the series, both vertebrae are very long as 

 compared with any of the living Delphinidae and are in that re- 

 spect most like those of Kentriodon. In other respects, as has been 

 pointed out in the foregoing remarks, these two vertebrae are so 

 unlike those of Kentnodon that the writer has no hesitancy in stat- 

 ing that they belong to a quite different type of porpoise. 



Measurements of the type vertebrae (in millimeters) 



Lumbar Caudal 

 Length ot centrnm 45 41 



Breadth of anterior face of centrum 26 31 



Height of anterior face of centrum 22 27 



Anteroposterior diameter of base of transverse process 25 26 



Length of base of neural arch 28 29 (?) 



Breadth of neural canal . 11 4 



Distance between perforations at base of transverse processes — 23 



