THE IDENTIFICATION OF BIRDS. 
PART I. 
By I. FINN, B.A., F.Z.S. 
Fig. 1. KIWI, OR APTERYX. 
| eee exact relationship of the various natural families of birds to each other has 
been long a matter of discussion among scientists, and will probably continue 
to be so. But the limits of the families themselves are well agreed upon, and it 
only remains to give for these brief diagnoses so that they may be readily 
recognised by external and easily appreciable characters. This task Dr. P. Chalmers 
Mitchell and I embarked upon together, but when it was about half completed the 
appointment of my coadjutor to the Secretaryship of the Zoological Society prevented 
us from working further together, and so I am reluctantly compelled to finish it 
alone, as Dr. Mitcheil’s multifarious duties preclude any further co-operation. 
The real difficulty im assigning any bird to its proper family lies in the great 
number of these families, which never have been, and perhaps never will be, 
satisfactorily combined into large “orders” such as accommodate the groups of families 
im mammals and reptiles. For the old arrangement of perchers, swimmers, and so 
forth has long ago been found to be unnatural, combining under certain broad 
resemblances of structure and habit families of birds which were really essentially 
different. These families; themselves, however, are not really hard to determine, and 
when they are once learnt any scheme for their combination into “orders” is more 
readily mastered. The points to which attention will especially be drawn are the 
situation of the nostrils and the extent of the gape of the mouth, and the scaling 
and webbing of the feet, points which hitherto have been rather too much neglected 
by ornithologists, both fxom a scientific and practically diagnostic point of view. 
Other points will of course be introduced when necessary, but bill and feet will 
separate iost families of birds satisfactorily. 
In studying the feet of birds it must be borne in mind that no more than four 
toes exist in any species (the “fifth toe” of certain fowls bemg merely a double 
monstrosity), and that in the usual arrangement of three in front and one behind 
the back toe is the first, corresponding to our own great toe, while the three front 
toes, beginning from the inside, represent our second, third, and fourth toes respectively. 
THE RATITE BIRDS. 
The comparatively small. number of species included under this name (derived 
from vatis, 2 raft, from the raft-lhke, because keel-less, condition of their breast-bone) 
are all incapable of flight, and usually of large size. Their lax hair-lke plumage 
will distinguish them at once, and, with the exception of the Kiwis, they have short 
beaks and no hind-toe. Taking the families in detail :— 
The Ostriches (if there be really more than one species), (Strwthionide), are 
diagnosed from all other birds not only by their pre-eminent size, but by having two 
toes only, both in front, these being the third and fourth. 
The Rheas (Rheide) have better-developed wings than any other Ratites, these 
being quite lage, covering the back, and folding in a Z-shape at the elbow and 
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