350 MR. W. H. FLOWER ON THE OSTEOLOGY OF THE SPERM-WHALE. 
the transverse processes, which points to a close affinity with /yperoodon and the 
Ziphioids. The lumbar and caudal regions also, in some characters, especially their 
short transverse processes, approximate to those of the same forms; the spinous pro- 
cesses, however, fall far short of the excessive height, and the bodies of the vertebre 
present but little of the peculiar elongation, so characteristic of those groups. 
Chevron Bones. 
Ten chevron bones were sent with the skeleton ; but it would appear from the distance 
to which these bones extend backwards, as ascertained with certainty on the detached 
tail described at p. 347, that fourteen is the complete number. By a careful comparison 
of the articular surfaces on the vertebrz with those on the different chevron bones, the 
missing ones were ascertained to be the fifth, sixth, and the thirteenth and fourteenth. 
The first (See Pl. LIX.) is represented by a pair of small styliform bones. They are 
not quite alike, the right being rather the longest,and the left much the thickest. 
They both end in a point, and are slightly hollowed on their inner side, and flattened 
externally. They fit most closely, by an expanded, rough, subcircular base, to the corre- 
sponding facets on the hinder margin of the body of the first caudal vertebra. The 
dimensions of these bones are :— 
| | Right. | Left 
inches. | inches. 
Hien et, os, ve Gebers Med tbc Mkov teks, Mees Mice 6r } 52 
Diamoteriat base. vets skeen Come tencrtsG Sincere PEP eed ey 288 
Diameter at middle, antero-posterior .......... | 19 23 
” xy ARATISVOTRO 6 «oF od 1% 5 dance “has | 1-5 
From the Yorkshire skeleton these bones are absent. In the Caithness specimen 
they are more massive and irregular in shape,and are completely ankylosed to the body 
of the vertebra. Their free extremities diverge from each other and project strongly 
backwards. 
In the succeeding bones (up to the fourteenth) the two lateral lamin are united 
below, and form a prominent spine. The second is comparatively small and narrow, 
and has the spine slightly developed. In the third the spine is very large, both long 
and broad, and truncated below. In the fourth it is somewhat shorter, but more mas- 
sive and rounded at the lower end. ‘The entire length of the second bone is 102", of 
the third 21", and of the fourth 20". The lower edge of nearly all the remaining bones 
has been cut off by a sharp instrument in preparing the skeleton; so I am not able to 
give their correct length or configuration. The surfaces for contact with the vertebrae 
are expanded, massive, rough, and hollowed; and many of them have imbedded within 
them separate epiphysial ossifications, more or less ankylosed either to the chevron 
bone or to the body of the vertebra. 
In both the Caithness and Yorkshire skeletons the number of the chevron bones is 
