AXIAL SKELETON OF THE PELECANIDZ. 345 
A detailed description has been given by Brandt in the ‘ Mémoires de |’ Académie,’ 
before referred to!, p. 127, with figures of the whole skeleton, the breast-bone, and a 
back view of the pelvis, in pl. 2. 
I have been able to make use of the following skeletons for the purpose of com- 
parison :—A mounted skeleton, No. 1180 (P. carbo), and a natural skeleton, No. 1182 ¢ 
(P. bicristatus), in the Museum of the Royal College of Surgeons; also a mounted 
skeleton, a disarticulated natural skeleton, No. 68. 8.16. 3 (P. carbo), a natural skeleton 
from Chili, No. 76. 9. 26. 16, a disarticulated skeleton, No. 56. 11. 14. 17 (P. brasili- 
ensis), and that of a small kind from the Upper Ucayle, No. 16. 3. 28. 17, all in the 
British Museum. 
I am also indebted to Professor Garrod for the loan of a specimen. 
The total number of vertebre, without counting the pygostyle, seems to be from 
forty-six to forty-nine. 
These vertebre are subdivisible as follows—eighteen cervical, two cervico-dorsal, five 
dorsal, five lumbar, two lumbo-sacral, two sacral, seven or eight sacro-caudal, and five to 
eight caudal, besides the pygostyle. 
There are constantly five dorsal vertebra, and twenty cervical and cervico-dorsal 
vertebre taken together; but there may be eighteen cervical and two cervico-dorsal 
vertebree, or seventeen cervical with three cervico-dorsals. The lumbar vertebre are 
generally five in number, but may be only four. The lumbo-sacrals may, by rare 
exception, be reduced to one, or augmented to three, There may be but one vertebra 
apparently distinguished as a sacral vertebra. The sacro-caudals and caudal vertebrae 
taken together are generally as many as fourteen; but they may be only thirteen, or as 
many as sixteen; and always either seven or eight of these ankylose with the pelvis, and 
so come to be reckoned as sacro-caudal vertebre. 
The whole axial skeleton, when compared with that of Su/a, is a somewhat yet denser 
structure; and the various ridges and processes are sharper and relatively more developed. 
Median hypapophyses are not only much more developed than in Sw/a, but even than in 
Pelecanus, especially in the anterior sacral region. Hyperapophyses are also relatively 
larger than in either of the former genera. The styloid rib-like processes are free, as 
in Sula, and even somewhat longer relatively, being decidedly more slender. 
Tue CervicaAL VERTEBRA. 
These vertebrae, when compared with those of Sula, present a very close resemblance, 
but are longer relatively and more hypapophysial, with a more slender and prolonged 
styloid rib (p. 35). They are more numerous than in Sula or Pelecanus; and thus the 
sudden change of form takes place over vertebrae more postaxiad than in those genera. 
The attas has its preaxial articular surface rather less circular, broader relatively 
dorsally, and narrower ventrally. There is an odontoid foramen ; but it is less decidedly 
1 See above, p. 315. 
