THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



185 



Vertebrae : 7, 15, 14, 24 -f- = 60 +; several lacking. The last present measures 

 4^" X 4-L" and is 2f " thick antero-posteriorly. Fifteen should perhaps be counted as 

 lurabars. It is uncertain. 



RIBS. 1 



The Ocean City whale has 15 pairs of ribs. The majority of specimens of B. 

 musculus thus far described have this number, as will be seen by reference to the 

 table on p. 181. Gervais, however, insists that the number should be 16 pairs, 

 and that when less are reported it is because the last pair is overlooked. This 

 hardly seems probable in view of the variability known to exist in all species of 

 cetaceans. It was not the case in the Newfoundland foetuses which I examined, 

 two of which had 15 pairs of ribs and one 16 pairs. 



In the Ocean City whale, the 2d, 3d, and 4th ribs have capitular processes. In 

 B. musculus, according to Van Beneden and Gervais (8, 215), the 3d and 4th ribs 

 are furnished with a neck (col). This information is probably from Malm. Of the 

 Hull museum skeleton Flower remarks (45, 412) : "The 2d and 3d ribs have both 

 well-developed capitular processes extending towards the bodies of the vertebrae, 

 longer and more slender in the third. In the 4th this process is nearly obsolete, 

 and absent in all the succeeding ones." 



The 1st rib in the Ocean City whale, as normally in B. mus<yulus, is single- 

 headed. It is to be remarked, however, that the 1st rib in the Ostend, Belgium, 

 skeleton, according to Dubar's figure and description, is double-headed (34, 38, pi. 8). 



The following table includes measurements of the ribs of various European 

 specimens and of the Ocean City, New Jersey, skeleton : 



BALJENOPTERA MUSCULUS (L.). EUROPEAN AND AMERICAN. RIBS. 



SCAPULA. 



The only illustrations of the scapula of the European Sulphurbottom accessible 

 are Dubar's (34, pi. 10), which is obviously inaccurate, and the figure copied by 

 Van Beneden and Gervais from Malm's illustrations of " B. Carolines" (8, pis. 12-13, 

 fig. 33). Outlines of these figures and of one of the scapulae of the Ocean City, N. 



1 No material is available for a comparison of the sternum of the European Sulphurbottom 

 with American specimens. Text-figures 49 and 50 show the form in two European examples. 

 1 Breadth at distal end, 9^ in. 



