ANATOMY OF MEGAPTERA LONGIMANA. 121 



Viewed in relation to the pedicle, a distinctive character is 

 afforded by lines drawn vertically up from the inner and outer 

 borders of the pedicle. The inner line, drawn from the con- 

 cavity of the border, corresponds in Megaptera to the inner end 

 of the articular process ; in B. musculus it cuts off about the 

 inner third of the process. The outer line, drawn from where 

 the pedicle leaves the body, would, in Megaptera, cut off the 

 inner third or fourth of the articular surface less and less back- 

 wards, so that on the 6th and the 7th line would fall at the 

 inner end of the process. In B. musculus the line would pass 

 at the outer edge of the process of the 3rd, and more and more 

 external to the processes as we go back. These differences 

 result partly from the articular process being in part placed in 

 B. musculus on the lamina, while in Megaptera they are placed 

 above the pedicle, and above the root of the transverse process ; 

 and partly from the greater breadth of the pedicle in B. mus- 

 culus. 



Pedicles of the Five Posterior Cervical Vertebrce. As seen 

 in Table II., the diminution in the breadth of the pedicles in 

 Megaptera, as we go forward in the dorsal region, is continued 

 to the 6th cervical (1| inch), in front of which there is very 

 little change. The forward diminution in the thickness of the 

 pedicle, from the dorsal region, ceases after the 6th cervical 

 ( inch), except on the 3rd cervical, on which it is slightly in- 

 creased. The greater size of the anterior articular process may 

 account for the pedicle of the 3rd being a little stronger than 

 that of the three behind it, although its transverse process is 

 the weakest. 



[The much greater breadth of the pedicles in B. musculus is related 

 to the greater size of the transverse processes they have to support. 

 Their relation to the sides of the bodies is much the same in both, 

 and the width of the canal is nearly the same in both ; their greater 

 width in B. musculus is gained by the greater breadth of the bodies 

 in it. Their forward narrowing goes on from 3| inches on the 1st 

 dorsal, and 3| on the 7th cervical, to 2| inches on the 3rd cervical. 

 But their thickness is less than in Megaptera, -f- inch against |-.] 



The appearance of less height of the pedicle in B. musculus is 

 deceptive, owing to its greater breadth, and to the breadth and 

 lowness of its connection with the transverse process. Measured 



along the middle to the middle of the anterior articular process, 



L 



