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tage in the struggle for existence. Thus it may be reasonably inferred that disuse, under the usual 
operation of the laws of nature, has, in process of time, produced the modification of structure which 
distinguishes this form from all other known Parrots and thereby occasioned this disability of wing. 
The sternum, which in all other birds of its class has so prominent a keel, is so completely altered 
that it presents almost a flat surface, although the symmetry of the skeleton does not appear to have 
suffered in any other respect. 
Prof. W. K. Parker says : — “ Like all those who glory in ‘ high degree,’ the Parrots have a poor 
relation or two to abate their pride. The Owl-billed Parrot (String ops habroptilus) of New Zealand 
is as lowly as ‘ the younger son of a younger brother.’ If birds were to be classified by the sternum 
only, then the Stringops should be put near the Apteryx and the Tinamou attached to the train of 
the Peacock.” 
The late Prof. Garrod has pointed out that the Parrots, as an order, are peculiar for the variation 
that occurs in their carotids, which show four different arrangements, and that Stringops is one of 
those forms in which the two carotids run normally *. 
Conformably also with the doctrine of natural selection, we have here another striking instance 
of the law of assimilative colouring, which obtains more or less in every department of the animal 
kingdom. Nature has compensated this bird for its helplessness when compelled to leave its hiding- 
place in the daytime, by endowing it with a mottled plumage so exactly harmonizing with that of 
the green mosses among which it feeds, that it is almost impossible to distinguish it. 
Although the existence of a large ground-Parrot was known to the early colonists of New Zealand 
from the reports of the natives, who set a high value on the feathers for purposes of decoration, it 
was not till the year 1845 that a skin of this bird reached Europe ; and this was purchased by the 
Trustees of the British Museum for the sum of £24. 
* The same distinguished anatomist, in one of his earlier papers on the muscles of Birds, pointed out that the ambiens may 
he present normally, or it may be differentiated in the thigh, but fail to cross the knee, being lost in the fascia over it, or it may 
be absent ; and he stated that in Stringops habroptilus it is present but does not cross the knee. In a subsequent paper ‘ On 
the Anatomy of the Parrots ” (P. Z. S. 1874, pp. 590-598) he says “ I have twice had the opportunity of dissecting Stringops 
liabroptilus. As a Parrot it is not so strikingly peculiar as many seem to think. Its wings are useless, and the carina sterni is 
correspondingly reduced, it is true ; but as points of classificational importance, I regard these as insignificant. The points of 
special anatomical interest which it does possess, however, are particularly instructive. The proximal ends of the incomplete 
furcula are well developed, so much so that it might at first sight seem that the symphysial ends are only lost in correlation 
with the excessive reduction of the powers of flight ; though this is probably not the case, because the allied similarly modified 
genera Euphema &c. do not keep to the ground. Further, in the Society’s specimen above mentioned, though the ambiens 
muscle did not cross the knee, yet its fleshy belly was well differentiated on both sides, its thin tendon being lost over the 
capsule of the joint. In the College of Surgeons’ specimen, however, this muscle was entirely absent in the only knee which 
was in a fit state for dissection, the other being much shot. It is only in the genus (Edienemus that I have elsewhere found a 
similar partial loss of the ambiens. The partial development of this muscle in this particular instance shows that the tendency 
to lose it is not of great antiquity ; and it is to be noted that there is no other Parrot with normal carotids in which any trace 
of an ambiens is to be found. These considerations suggest, what may perhaps be the case, as is suggested by the peculiarities 
of their geographical distribution, that Agapornis may be the representative among the normal- carotid Parrots of the Platy- 
cercine branch from the A rinse, whilst the Stringopime proper (including Oeopsittaeus, Melopsittacus, and Euphema) are more 
direct continuations of the main stem, Stringops itself being the nearest living representative of the common ancestor of the 
whole suborder.” And in a postscript (dated Dec. 8, 1874) he adds On the 25th of last month, from the death of one of the 
specimens of Stringops habroptilus, recently purchased by the Society, I have had an opportunity of dissecting a third individual 
of the species. In it the ambiens muscle is complete, of fair size, at the same time that it crosses the knee as in Psittacus. This 
makes me feel more convinced that the arrangement indicated by me is the correct one, and that the main stem has given rise to 
three instead of two branches— the Stringopinm being the nearest representatives of the ancestral form, some of its members 
(, Oeopsittaeus , Melopsittacus, Euphema, and Cyanorhamphus ) having quite recently lost, whilst Stringops itself is just now on the 
point of losing the ambiens muscle. It is, however, quite possible, if external resemblances and geographical distribution are 
left out of consideration, that Stringops must stand as the sole representative of the Stringopinse, thus conforming with generally 
received ideas.” 
