1349 Tam Zool ore. Lenn Af 
41 
MUSCULAR SYSTEM. 
THE former part of this memoir on the Anatomy of the Apteryx australis* in- 
cludes the description of the osteology and splanchnology, with the male organs of 
generation ; the present part is devoted to the illustration of the myology of the same 
rare and anomalous bird. The specimens which I have dissected for that purpose were 
afforded me by the Earl of Derby, President, and by Mr. George Bennett, F.L.S., of 
Sydney, Corresponding Member of the Zoological Society, to whom I am much in- 
debted for such valuable opportunities of completing this monograph on the Apteryx. 
The muscular system offers a subject of peculiar interest to the Comparative Anatomist 
when studied in a species which, in its general proportions and habits of life, deviates 
in so extreme a degree from the rest of the circumscribed and well-marked class to 
which it belongs. It is also a department of the anatomy of birds which, from the mi- 
nute attention and length of time required for its accurate investigation, has been com- 
monly passed over in anatomical monographs of species, but which the rarity of the 
Apteryx and the excellent state of preservation of the specimens dissected have both 
stimulated and enabled me to pursue with a degree of care which will be found, I trust, 
if tested by subsequent dissection, to have left little to be added to the myology of the 
species. 
In the application of the facts detailed to the higher generalizations of the philosophy 
of organized bodies, it will be found that the unity of the ornithic type is strictly pre- 
served, though under the extremest modifications ; the characteristic peculiarities, for 
example, of the muscles of the spine and those of the wing, are all present, but the pro- 
portionate development of these classes of muscles is reversed, the spinal muscles being 
at their maximum, the alar muscles at their minimum of development. Very interest- 
ing peculiarities are likewise manifested by the muscles of the skin, with which I propose 
to introduce the details of the muscular system of the small Struthious bird of New 
Zealand. 
Musc tes oF THE SKIN. 
No detailed description of the muscles of the skin in Birds has been given either in 
the systematic works on Comparative Anatomy, or in particular treatises ; these muscles 
appear indeed in general to be too irregularly or too feebly developed to have attracted 
* Transactions of the Zoological Society, Vol. II. Part 4, p. 257. 
G 
52 277 = Zo 
