63i R- W. SHUFELDT 



certain limits, they hold true for members of the same family, and 

 in several families differ very widely. 



CONCLUSION 



The extinct fossil bird which has been very fully considered in 

 the present paper was one rather smaller than the North American 

 ruffed grouse {Bonasa umbellus), to which it was quite closely 

 affined. Were it in existence today, its place would have been in 

 the family Tetraonidae, and near Bonasa, Canachites, and Lagopus, 

 with which forms it holds many, indeed all, tetraonine skeletal 

 characters in common. That it was a bird possessing strong volant 

 powers is abundantly shown by the deep keel to its sternum, and 

 the powerful development of its pectoral arch and wing; these offer 

 ample evidence of this fact. Without doubt it had a flight quite 

 coequal with that of any ordinary grouse. 



This form was in no way related to the Rallidae, or any similar 

 group, and certainly not to the gallinules. Moreover, when we 

 come to find early Eocene forms of the Tetraonidae that exhibit in 

 their skeletons a departure from the true tetraonine stock, it will 

 not be a form of bird having in its skeleton paludicoline characters, 

 and particularly not ralline ones. No such alliances have existed 

 at any time in the world's history. 



Annectent forms, possessing a good proportion of tetraonine or 

 galline characters in their generalized organizations, will also exhibit 

 skeletal characters connecting them with the pigeons and their 

 near alHes {Columbae), and such birds are still found to exist in the 

 world's avifauna, as witness the sand grouse and others {Syrrhaptes 

 paradoxus). In fact, the pigeons and fowls, as we know, possess 

 many morphological characters in common at the present day. 



As to finding the fossil remains of a true gallinaceous bird in the 

 Green River shales of Wyoming (Middle "Eocene), it need not sur- 

 prise anyone, for true grouse forms occurred in corresponding for- 

 mations elsewhere, not only in this country but in Europe. This 

 is likewise true of the Phasianidae, a matter which I have abund- 

 antly proved in a memoir on the subject recently pubHshed entitled 

 "Fossil Birds in the Marsh Collection of Yale University," and 

 published in the Transactions of the Connecticut Academy of Arts 

 and Sciences, XIX. (February 191 5), i-iio. 



