98 PROFESSOK STRUTHERS. 



with diminution immediately behind and before. The eye does 

 not detect that the first three kimbar are equally wide, nor 

 would the eye detect so great a diminution as 6 inches from 

 the 14th to the 8th dorsal. 



[23. Transverse Processes in B. musculus compared with those 

 OP Megaptera. 



The transverse processes differ much from those of Megaptera, 

 in expansion of their outer two-thirds, in being much thinner, and in 

 being very little turned upwards in the dorsal region. 



24. Dorsal Region. — Orirjin. — The root common to the pedicle 

 and the transverse pi'ocess on the first four is more oblique than in 

 Megaptera. On the 7th, the pedicle and the process are as distinct 

 as on the 8th of Megaptera. Behind this, as seen from above, the 

 processes spring from lower on the bodies than in Megaptera. This 

 is owing to their thinness. Seen from below, they do not spring so high 

 from the bodies as in Megaptera, but from the 4th to the 1 3th their line 

 of origin is slightly convex upwards. At the 1.5th, the process is thin 

 enough to have fallen qviite to the level of the middle of the body. 



Direction.— Th.e first is straight. The three first are decidedly 

 concave above. Viewed from above, the processes appear to the eye 

 to rise outwardly from the 5th to the 12th, but it is from the 7th to 

 the 13th that the outer end of the process is really higher than the 

 inner part, the 13th very little. The rise above the costal fossa 

 renders the outer half concave. From the 6th, diminishing back- 

 wards, the inner half of the process is rather convex. A line from 

 tip to tip of the transverse process of the 10th shows a rise of 1|- 

 inch from the neck to the tip of the process. The line is on a level 

 with the body' at its hinder edge and 1|- inch below the articular 

 process. The concavity is about \ inch deep. On the 7th it is twice 

 that, the depth increasing forwards owing to the inward rise of the 

 process to the articular process. Viewed from below, the processes 

 rise a little outwardly from the 7th to the 13th. T\\e forivard direc- 

 tion of the processes is greater than in Megaptera. The distances to 

 which the processes pass in front of the plane of the body of their 

 vertebra are — the 1st, 4^ inches ; the 3rd, b}j ; the 5th, 3| (angle 

 40°) ; the 7th, U ; the 9th, 1 inch. The 10th"is nearly straight out. 

 The backward direction begins on the 11th and 12th. The back- 

 ward direction of the posterior border begins on the Sth. On the 

 llth, the most prominent parts of the process are, respectively, \ inch 

 behind the front of the body and J- inch behind the back of the body. 

 Behind this, the backward direction of the processes is much less 

 than in Megaptera. The posterior part of the process is 1 inch 

 behind the body on the 13th (angle 5°); on the 14th, ^ inch; on 

 the 15th, it is | inch in front of the back of the body. 



Form. — The prismatic form is well marked on the 3rd and 4th, 

 un their inner half, and throughout on the Sth and 6th, especially 

 at their outer part. Behind the 6th the processes grow thinner and 

 tlnnner by the gradual disappearance of the lower edge of the prism. 



