26 
CENTKAL HALL. 
Bay III. 
General 
structure 
of Birds. 
Contents of 
remaining 
Bays not 
completed. 
6. The horns of oxen, goats and antelopes, consisting of a 
hollow conical sheath of horn, covering a permanent projection 
of the frontal bone (the horn-core). 
7. The antlers of deer, solid, bony, generally branched, projec- 
tions, covered during growth with soft vascular hairy skin, shed 
and renewed annually. 
The other systems of organs of the class will occupy the 
remainder of this bay. 
Bay Ko. III. is devoted to the class of Birds. In the first 
wall-case the principal facts in the osteology of the class are 
shown. Sections of bones exhibit the large air cavities within ; 
a complete skeleton of an eagle, with the bones separated and 
named, and mounted skeletons of the ostrich, penguin, pelican, 
vulture, fowl, &c., show the chief modifications of the skeleton. 
The apteryx shows the smallest, and the frigate bird the largest 
bones of the wing, the correspondence of which can be readily 
traced by means of the labels attached to them. The under 
surface of the skulls of various birds are shown with the different 
bones coloured to indicate their limits and relations, followed 
by a series of the different types of sternum or breast-bone. 
The table-case in the middle of the bay contains illustrations 
of the external characters, the beak, the feathers and the tail, as 
well as of the fore and hind limbs, or wings and feet. 
Bays lY. and Y. completing the west side of the hall, will, 
in a similar manner, show the most important points in the 
structure of reptiles and fishes. 
Of the bays on the east side of the hall, iSTo. YI. is for the 
illustrations of the articulated classes, Crustacea, Arachnida, 
Myriapoda and Insecta, as well as of the Annulosa and Yermes, 
No. YII. for the Mollusca, Echinodermata, Ccelenterata, Porifera 
and Protozoa ; and the remaining three, YIIL, IX., and X., for 
the morphology of the vegetable kingdom: the first containing the 
Cryptogams, the next the Gymnosperms and the Monocotyledons, 
and the last the Dicotyledons. By this arrangement the lowest 
or simplest forms of animal or plant life, those on the border 
land, as it were, of the two kingdoms, will be brought into 
contact, and at the two ends of the series, in Bays I. and X., 
will be found the groups which show in the highest degree 
the special attributes of the division to which they belong. 
