88 THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



and the character of the dorsal line. He appears to have intended also to point 

 out osteological differences between tectirostris and tuberosus, but the language 

 employed is so ambiguous that this is uncertain. There is, furthermore, a doubt 

 whether he ever really examined the skeleton of tuberosus, as will be explained later. 



The position which I take regarding tectirostris is (1) that Cope at the time he 

 first described it did not evince any knowledge of the fact that one kind of Finback 

 is common on the east coast of the United States, and that (2) there is, therefore, no 

 probability that he intended to establish a second species similar to, but somewhat 

 different from, the common species ; consequently, that (3) the type-specimen of 

 tectirostris does not merit any more attention than other specimens of the common 

 Finback, unless on comparison of them all together the type of tectirostris seems to 

 stand apart from the others. As to whether the latter condition is found will be 

 fully considered later. What we really wish to ascertain is whether the com- 

 mon Finback of the Atlantic coast of the United States is the same as, or differ- 

 ent from, B. pJiysalus (L.) of Europe. The type-skeleton of B. tectirostris is 

 figured on pis. 1, 2, 4, 5, and 6. 



The following measurements of the type-skeleton made by myself in 1900 

 include those made uniformly for all the specimens examined, and others which 

 appear to be of importance in this particular case : 



SIBBALDIUS TECTIROSTRIS COPE. (TYPE.) 

 Skull: Inches. 



Total length (straight) 121.0 



Greatest breadth (squamosal) 54.0 



Breadth of orbital process of frontal at distal end 8.75 ' 



Length of rostrum (straight) 80.75 



Breadth of rostrum at middle (curved) 26.5 * 



Length of nasals in median line 7.5 



Breadth of the two nasals at the distal end 5.5 " 



Length of mandible, straight 1 1 i.o 



curved 1 20.0 



Depth of mandible at middle 9.5 



Skeleton : 



Greatest breadth of axis 25.0 



" height " " 13.25' 



Depth of centrum of axis 7.0 * 



Greatest breadth of ist dorsal 22 -75 



height " " " 13.25 



Depth of centrum of ist dorsal 7.25 " 



Greatest breadth of ist lumbar 32.0 



height " " " 21.5' 



Depth of centrum of ist lumbar 7.75 7 



Greatest breadth of ist caudal 24.0 * 



height " " " 21.0+' 



Depth of centrum of ist caudal 9.25 ' 



Greatest breadth of scapula 3 2 -75 



depth " " 19.5 



Length of acromion, inside (straight) 7.0 



Length of radius, with epiphyses 24.0 



Length of radius, without epiphyses 23.0 



" ulna, with epiphyses 22.25 



without epiphyses 21.5 



" " humerus (straight) 15.0 



1 Tip to tip, least. * Median = 12 25 in. ' Posterior. 



1 As mounted. * Median, posterior. "Twice one half. 



' Opposite distal end of inner margin. ' Median, anterior. 'Anterior. 



