SOME OF THE OUTLIERS AMONG BIRDS. 761 



existed in bygone ages, and had been the parents of a varied and 

 varying offspring our fellow-creatures of to-day." 



" Classification for the first time was something more than the 

 expression of a fancy. Not that it had not also its imaginative 

 side. Men's minds began to figure to themselves the original type 

 of some well-marked genus or family of birds. They could even 

 discern dimly some generalized stock whence had descended 

 whole groups that now differed strangely in habits and appear- 

 ance their discernment aided, may be, by some isolated form 

 which yet retained undeniable traces of a primitive structure. 

 More dimly still, visions of what the first bird may have been 

 like could be reasonably entertained ; and passing even to a 

 higher antiquity, the reptilian parent, whence all birds have 

 sprung, was brought within reach of man's consciousness." 



When all this came to pass it was those very isolated forms 

 the so-called " outliers " among birds to which Prof. Newton 

 alludes in the last paragraph, that then came to be regarded with 

 a peculiar interest by the scientific ornithologist; and, although 

 at the present writing there is by no means a unanimity of opin- 

 ion as to the position many of them occupy in the system, they 

 nevertheless at once threw a powerful light upon the whole field 

 of ornithology. Ornithotomists everywhere, the world over, care- 

 fully investigated their anatomical structure, and groups of birds 

 long thought to be widely separated were seen to be, through 

 these forms, more or less nearly related to each other, and the 

 fact as a whole was demonstrated beyond all cavil that the class 

 Aves had arisen from primitive reptilian stock. 



Without further dwelling upon this phase of the subject, we 

 will say here that it is the object of the present article to call 

 attention to some of the more prominent species of birds that, to 

 a greater or less extent, are considered to represent these " out- 

 liers" of the class. Although hardly to be regarded as belonging 

 among them, the very interesting group of forms that we com- 

 monly designate among them as the " ostrich group " are im- 

 portant, inasmuch as through them we are enabled, by the aid of 

 many fossil and subfossil types, to trace birds directly back to 

 some of their reptilian stock. Among the existing ostrichlike 

 types we have the Apteryx or knvi, of New Zealand, a bird now 

 supposed by some of our best authorities to have kinshiiD with 

 the rails. Then there are the emeus and cassowaries, rhea, or the 

 South American representative of the ostriches, and, lastly, the 

 true ostriches themselves.* 



* The great moas (Dinornis) of New Zealand are now extinct, though we have their 

 remains in plenty. This is the case also with the huge ^pyornis of Madagascar, the Gas- 

 iornis, the Struthiolitlius of lower Russia, and the curious fossils found in the Siwalik rocks of 

 VOL. XLVI. 5*7 



