280 THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



throws doubt on their authenticity, since they plainly belong to Balcenoptera and 

 not to Megaptera. However, the error is probably a clerical one. 



The two pieces are thin and have the surface roughened by longitudinal and 

 transverse raised lines. One piece (No. 13981) has a length of 23 in., and a breadth 

 at the base of about 8.5 in. The second piece (No. 13982) is 28 in. long, with a 

 breadth of 9.5 in. at the base. The former has t\vo light-colored, translucent 



O * 



longitudinal bands, about ^ in. wide, near the outer margin. 



As no other material, representing this species, which passed through Scam- 

 mon's hands, is now accessible, I have endeavored to find out what the " Common 

 Finback " of the Pacific coast really is from other sources. The material at com- 

 mand is meagre and consists only of (1) a skeleton formerly owned by Cope and 

 now in the museum of the Wistar Institute, Philadelphia (see pi. 6, fig. 4 ; pi. 28, 

 figs. 5, 6) ; (2) measurements of a specimen captured off San Clemente Id., Cal., in 

 1895, and exhibited in Celoron, New York, in 1896. 1 



The Wistar Institute skeleton is that of an adult animal, which, according to 

 a record on a piece of paper found in the box which contained the skeleton, was 68 

 ft. long. The mounted skeleton is 62 ft. 10 in. long. It is a very fine and practi- 

 cally perfect specimen. The whalebone is slate-colored, streaked longitudinally 

 with whitish, and the right anterior 6 or 8 inches all white. This is characteristic 

 of . physalus. The vertebral formula is as follows : C. 7 ; D. 15 ; L. 15, Ca. 23 

 + = 60 +. The last caudal is about the size of an apple. There are fifteen 

 chevron bones. The following measurements were taken with the aid of Dr. Green- 

 man, to whom my best thanks are due : 



SKELETON (MOUNTED) FROM WEST COAST OF NORTH AMERICA IN THE WISTAR INSTITUTE, PHILADELPHIA. 



(BELONGED TO COPE.) 



Total length of skeleton, mounted 62 ft. 10 in. 



Length of skull, straight, without premaxillse 15 " 6 ' 



Breadth" " greatest 7 " 9 " 



Length of rostrum, without premaxillae 10 " 6 



Breadth" at middle 3 " Si " 



Length of mandible, straight 15 ' 4 " 



curved 16" 5" 



Breadth of orbit, least i of 



greatest 20 



Breadth of scapula 4 '' 2 " 



Height " " 2 " 7 " 



Length of radius 2 " 9^ ' 



" " ulna, least 2 " 6J " 



" " " greatest 2 "i^" 



Breadth of axis 



Depth of mandible at middle i " i J 



Length of acromion of scapula, greatest 14 " 



" coronoid 6 " 



1 For these measurements I arn indebted to Prof. H. L. Osborn, St. Paul, Minn. 



