156 MR. W. H. FLOWER ON THE SKELETON 
The stylo-hyals have the usual form, and are 4”°5 long, and 0-6 in greatest diameter. 
The spinal column, which is quite complete, consists of fifty-one vertebrae, seven 
belonging to the cervical, twelve to the dorsal, ten to the lumbar, and twenty-two to 
the caudal region. The respective lengths of these four regions in the articulated 
skeleton are 3 inches, 174 inches, 163 inches, and 30 inches. 
In the cervical region, the atlas and axis are united, and the remaining vertebre are 
free, as appears to be the rule in the genus Delphinus. 'The component parts of the 
conjoined mass formed of the first two vertebra can be readily defined. The bodies are 
thoroughly confluent, though a superficial groove marks the limit of each with tolerable 
certainty. The arches in their first part, or pedicle, are distinct, and have between them 
a considerable oval aperture for the transmission of the second spinal nerve. Above 
this, opposite the zygapophysis, they are firmly united; the laminz are then separated 
on either side for a space of half an inch by a linear fissure; and, finally, the spines are 
completely confluent. ‘This conjoined spinous process is high, massive, sloping back- 
wards, strongly ridged on its median upper or anterior border, and with a rounded and 
somewhat depressed and truncated apex. The pedicle of the arch of the atlas is very 
much thicker than that of the axis, and on its anterior border has a deep notch, almost 
converted into a foramen on the left side, for the passage of the first (the suboccipital) 
spinal nerve. Both atlas and axis have a single transverse process on each side, that of 
the former long, stout, rugged, rounded at the end, and directed slightly downwards 
and backwards. The transverse process of the axis is a small, rough, and rather com- 
pressed tubercle, placed nearly on a level with the root of the last, and directed some- 
what upwards as well as backwards. The dimensions of these vertebra are :— 
inches. 
Breadth of articular surfaces on atlas for condyles . . . . 40 
Breadth between tips of transverse processes of atlas. . . . 5:7 
Breadth between tips of transverse processes of axis . . . . 3°6 
Greatest breadth of spinal canal, inside arch of atlas. . . . 18 
Greatest breadth of spinal canal, inside arch of axis . . . . 15 
Height of spinal canal, insideatlas . . . . . . ...-. 16 
Height of spinal canal, inside axis; 2 9: =: 3 3 » “os 29 
Breadth of body of axis at posteriorend. . . . .. . . 17 
Height of body of axis at posteriorend . . . .... . 6 
Height from lower surface of body of axis to apex of spinous 
DWE 9G 6 fo bo rae eeacaade: ctr Saprerice ed AY 
Length of upper or anterior edge of conjoined spinous process 2°1 
The remaining cervical vertebre have greatly compressed subcircular bodies. The 
under surface of each has a fringe of rough exostoses growing on each side of the 
middle line, and leaving (as seen in the figures, Pl. XVIII.) a deep notch at this part. 
