ANATOMY OF MEGAPTERA LONGIMANA. 



107 



30. Table V. — Measurements of the Transverse Processes of 

 the Cervical Vertebrce, in addition to those contained in 

 Tables II. and III, given in inches. 



31. The Atlas. — Anterior Aspect. — The groove between the 

 condyloid cavities is wide. This might seem to be a distinctive 

 character in contrast with the narrowness of the groove in B. 

 musculus, as seen in four of my specimens. In two of them it is 

 reduced to the condition of a mere median furrow. But in the 

 50-feet-long B. muscuhis the width is not much less than in the 

 Megaptera. In the latter the width is — below, which is also the 

 narrowest part, 1| inch ; at middle, If ; above, 2|. In the B. 

 musculus, the corresponding measurements are, Ih, 1|, and 2^ 

 inches ; the narrowest part, towards the lower end, 1^. The 

 widest in the other four specimens of B. musculus is f inch, 

 and the groove has that width nearly all along. In both the 

 Megaptera and the 50-feet-long B. musculus the furrow for the 

 capsular ligament of each condyle is seen at the edge of the 

 wide groove. In the dissection (1872, loc. cit., p. 14) I found 

 the median interval so narrow that the two capsular ligaments 

 seemed to have coalesced, and the median septum thus formed 

 to be disappearing, but I could not be quite sure that the 

 seeming partial disappearance of the median septum was not 

 due to giving way of the parts. The narrowing of the space 



1 The weight of the first caudal vertebra is, iii Megaptera, 304 ounces, in tlie 

 B. musculus, 368 ounces. 



