MR. W. K. PARKER ON THE OSTEOLOGY OF BALANICEPS REX. 339 
even in very old birds. The same thing occurs in Gannets and in Cermorants. In 
the Secretary Vulture and in the White Pelican there is this claviculo-sternal articu- 
lation ; but it becomes anchylosed in old age. In young Cranes—e. g. Grus antigone— 
this joint may be seen; but in full age, when the trachea has gone some distance into 
the sternum, it is entirely obliterated. We have not seen this structure in the some- 
what aberrant Balearic Crane, nor in the Agami (Psophia crepitans), in which bird 
unmistakeable Gallinaceous characters are present. But in this young Baleniceps not 
only is all trace of a joint gone, but the amount of ossification and the actual strength 
of this part are very great indeed ; it is a seven-times strengthened anchylosis. The upper 
surface of the sternum is deeply and evenly concave, its depth in the mid-part being one 
inch and a quarter, whilst the same part is only a line deeper in the Adjutant. These 
two birds agree also in the number of large pneumatic holes, especially at the anterior 
and middle region, and between the five hinges for the heemapophyses on the upper 
margin of the sternum. In some of the Storks there are very small rudiments of a pair 
of sub-mesial emarginations besides the large lateral ones, which are constant. 
In Baleeniceps, however, these notches are nearly half an inch broad, leaving between 
them a xiphoid mesial process three lines wide at its extreme end. The outer notch is 
nine lines across, its external outline being the inner margin of the long narrow hypo- 
sternal process ; the upper and external margin of this process running forwards to the 
joint for the ‘sacral’ hemapophysis, is elegantly sigmoid. The great length of the 
hyposternal process (twice as long as that of the Adjutant) reminds us very strongly 
of the Rails and Coots, and still stronger Ralline features will show themselves towards 
the end of our task. The sub-mesial emarginations (very common in birds, but not 
present in the typical Ardeinz) tell us of another Wader with strangely modified 
jaws—viz. the Spoon-bill, a bird which seems to stand, in Nature, between the Storks 
and the Ibises. The very thick strong keel of the sternum passes on to the end of the 
bone ; in the Totipalmate—e. g. Pelican, Gannet, &c.—it only reaches half-way. In many 
birds—e. g. the Boat-bill, Herons, Storks, Cranes, Geese, &c.—the rami of the furculum 
are flat at the upper end, and passing within the head of each coracoid are there arti- 
culated. But in many other groups of birds—e. g. the Baleeniceps, Diurnal and Nocturnal 
Raptores, Swifts, Goat-suckers, and different genera of the Totipalmatz, as the Cormo- 
rants, Gannets, and Pelicans—the rami of this bone expand and become very thick 
before passing between the coracoids. In these latter cases the outer thickened part 
of the furculum forms an oval flat synovial surface which articulates with a similar sur- 
face on the front of the head of the coracoid, whilst the inner part of the ramus passes 
on, flat and triangular, to articulate with the inner side of the head of the coracoid. 
Measured in astraight line the symphysis of the furculum of the Baleniceps is 33 inches 
from its inner tip. These upper ends are 3 inches apart and the width across the thick 
anterior articular processes is 33 inches. It is therefore U-shaped as in the wide-bodied 
Storks, and not V-shaped as in the flat-bodied Herons. In the Pelican the enlargement 
