232 Transactions — Zoology. 



short legs, and the presence of a hind toe elevated above the level of the 

 others, shows an approach to the Gallinaceous order, while their long bil], 

 with its slightly swollen tip, resembles in some measure that of the Scolopacidce^ 

 which have also the same habit as the kiwi of feeling about on the ground 

 with their bill. Gallinago pusilla moreover lives in holes, and only comes out 

 at night (Travers, see Art. xxii). 



Thus the Apterygidce have a more generalised structure than the other 

 Struthious birds ; they therefore belong to an older type, and cannot with any 

 degree of correctness be said to represent the extinct race of moas. The 

 relations between the second family, or the Struthiones proper, are very 

 complicated, but Dinornis, which alone concerns us here, appears to be 

 intermediate between the rheas of South America, and the emus and casso- 

 waries of Australia and the adjacent islands. It approaches the rhea in the 

 structure of its egg-shell and in having only three pairs of sternal ribs, 

 while the emu, the cassowary, and also the kiwd, have four, and the ostrich, 

 five pairs. In the structure of its feathers, and in the shape of its pelvis and 

 skull the moa approaches the emu. The Struthious birds exhibit a type of 

 structure intermediate in many respects between the Carinate birds and the 

 extinct Dinosaurians, and this leads naturalists to suppose that they are but 

 the remnant of a race that once spread over the whole earth. About twelve 

 species are known outside New Zealand j while here, besides our four species 

 of Apteryx, Professor Owen has determined fourteen species of Dinornis, three 

 of Aptornis, and one of Cnemiornis, thus making a total of twenty-two sj^ecies 

 of Struthious birds, belonging to four different genera, living in New Zealand 

 only a few hundred years ago, that is to say, nearly twice as many as are 

 found in all other parts of the world put together. 



Probably, however, some of Professor Owen's species of Dinornis are but 

 the young of others, and it seems to me very doubtful whether Aptornis and 

 Cnemiornis should be regarded as Struthious birds at all. It is evident that 

 these two genera are closely related, and if the wing bones placed upon 

 Cnemiornis calcitrans really belong to the legs of the same bird we must 

 suppose that the sternum had a keel sufficiently developed to support muscles 

 of a size proportionate to the wings ; for although we can understand how the 

 kakapo (Stringops), belonging to an order of deeply keeled birds, may have 

 lost, by disuse of the pectoral muscles, the keel on its sternum, we cannot 

 possibly explain how a Struthious bird could have had large wing bones 

 developed unless it had also sufficiently powerful muscles to use them,, I also 

 observe that Aptornis defossor now wears a skull similar to that of the late 

 Dinornis casuarinus, which skull Mr. W. K. Parker says undoubtedly 

 belonged originally to a Notornis. But omitting these two genera, and 

 making a due allowance for doubtful species of Dinornis, the great number of 



