94 MR. K E. BBDDARJ) o\ THE 



in these animals. Nor is there apparently any room on that bone for the articulation 

 of a rib lying in front of this. This is a condition quite curiously the reverse of that 

 which often obtains in Rorquals (and other Cetacea), where the first rib is two-headed 

 and, indeed, partly double through its extent, being apparently formed by the union 

 of the ordinary first rib and a cervical rib. In Neobakena the ribs are decreasing in 

 number, and in consequence the first dorsal is small. It is, however, in the fully-grown 

 animal incomplete above, as it is in the immature skeleton, where the neural arches 

 do not meet. This latter fact is duly noted by Hector. 



It has been mentioned that the first six dorsal vertebrae only, and the last of these 

 hardly, have the transverse processes arising from the neural arch itself. In Balwna 

 the series of vertebrae in which the transverse processes arise thus is a longer one. 

 The first ten dorsals in Balmna austrcdis are provided with transverse processes which 

 definitely arise from the neural arch ; after that point they more and more distinctly 

 arise from the centrum of the vertebra. The arrangement in NeohalcBna is more 

 like that of Bakenoptera. In Balmnoptera kiticeps (1 = B. sihbakli) the sixth dorsal 

 vertebra has a transverse process arising from the centrum. The same appears to be 

 the case with Balcenoptera rostrata. 



The Scapula. 

 The scapula (PI. VII., Sc.) presents considerable difi'erences of form in the two 

 specimens. In the younger specimen it is much as was figured by Sir James Hector. 

 The bone is very elongated and not at all high. The highest point, moreover, is not 

 the middle of the superior border of the blade. The shape, in fact, is far from regularly 

 fan-like. A series of measurements showed that the anterior end of the upper border 

 is the highest part of the scapula. It is slightly depressed in the middle. So very 

 much does the posterior border slope directly backwards from the glenoid cavity, that 

 it seems to be almost in a straight line with it and with the acromion. Though I have 

 seen no scapula in any allied form in which this is the case, it appears that even in 

 Balcena, which has a particularly high scapula, the acromion is actually in the same 

 straight line, or very nearly so, with the posterior border of the shoulder-blade. Hector 

 has observed this, but has not emphasized the fact that the acromion and the posterior 

 border of the scapula are in the same straight line and that there is so far no diver- 

 gence from the characters of that bone in other Whalebone Whales. As to the elonga- 

 tion of the shoulder-blade, I found that the measurements of length and extreme 

 height (not, as already mentioned, in the middle of the bone, but near to the anterior 

 end, and, moreover, an oblique line ending at the middle of the glenoid cavity) are for 

 the right-hand bone 12| inches as against 7 inches in height. The left-hand scapula 

 was a little, a very little, different. The corresponding measurements were 13 and 7. 

 Taken in the middle of the superior border and drawn at right angles to that border 

 down to the margin of the glenoid cavity, the diameter of the scapula was not more 



