1885.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 585 



admissible. In M. Eectori, as figured by Professor Flower, the pre- 

 maxillary foramen lies in a groove, which is considerably prolonged 

 anteriorly. In our specimen the groove extends behiud but not in front 

 of the foramen. The premaxillse themselves begin to assume a per- 

 pendicular position immediately in front of the foramen. In these re- 

 si>ects the Bering Island specimen shows some affinity to M. Grayi. The 

 lateral expansion of the proximal ends of the premaxillse is relatively 

 less in 31. Hectori, much less than in the other species. The extension 

 of these bones on the horizontal surface of the maxilla opposite the 

 nares is much less than in M. Hectori. The palatine bones are well 

 developed and extend in front of the pterygoids on the "palate." The 

 vomer is visible in the middle third of the lower surface of the beak, as 

 in M. Hectori. The exposed portion is 66 millimeters in length. 



Viewed from the side, the contour of the occi])ital in the Bering Island 

 specimen is seen to be very decidedly less convex than in M. Hectori^ 

 as figured by Professor Flower. The occipital would appear to be flat- 

 ter than in any of the known species of the genus ; superiorly it is 

 concave. Though the sides of the beak are much broken, it is evident 

 that there is no basi-rostral groove in this species. 



A section of the beak at the middle has an outline quite different 

 from any of those figured by Professor Flower (I. e., p. 422). Omitting 

 the intermaxilla?, which stand vertically, the outline of the remainder 

 of the section is approximately a circle. 



As this species appears to be distinct from any hitherto described, I 

 propose for it the name of Mesoplodon Stejtiegeri, in honor of my es- 

 teemed friend, the eminent naturalist. Dr. Leonhard Stejneger. 



Diagnosis of Mesoplodon Stejnegeri, sp. nov. 



External form unknown. 



Skull. — Brain-case little less than half the length of the skull. No 

 basi-rostral groove. Premaxillary foramen posterior to the maxillary 

 foramen. Premaxillarj^ bones not grooved in front of the foramen, as- 

 suming a nearly vertical position anterior to the middle of the beak; 

 not greatly expanded laterally back of the nares. Occipital bone plane 

 above the condyles, concave at the vertex. Exposed portion of vomer 

 less than one-fifth the length of the beak. 



Habitat: Bering Sea. 



Washington, September 25, 1885. 



A NOTE UPON THE HYPEROODON SEMIJUNCTtTS OF COPE. 

 By FREDERSCK W. TRUE. 



The skeleton upon which Professor Cope based his Hyperoodon semi- 

 junctus having recently been transferred, through the courtesy of Dr. 

 G. E. Manigault, curator of the Charleston College Museum, to the 

 national collection, I have taken pains to examine it with the special 

 view of determining if possible the identity of the species. 



