THE FOSSIL AVIFAUNA OF THE 
407 
latter that the pneumatic fossae are to be seen, Avith tlie openings at their bases 
leading downwards. Noav in Atiser albifrons the pneumatic holes are upon the 
outer aspect of the limbs of the os furcula, the reverse of the case in the Swans, 
including Cygnus paloregomis of Cope, with Avhich I have comjiared them all. But 
either free extremity of the os furcula in Cygnus paloregonus is long and pointed, 
being narrow vertically, and thickened transversely as we approach the extremity. 
It also lacks the peculiar process upon its upper border, so characteristic of 8(Jine 
Geese and nearly all Ducks. In the Swans, of course, the lower mesial portion ol 
the os furcula is very much modified so as to allow of the passage of the trachea 
into the sternum. Nothing of that kind existed in Anscr cmdoiii Avhere the lower 
mesial part of the os furcula is almost exactly as we find it in Atiser albifrons. The 
upper free end of a clavicle in A. condoni also differs very much from that bone in 
the Swans, for it is inclined to be deep vertically, compressed transversely, Iduntly 
pointed distally, and possessed the peculiar process seen in A. albifrons upon its 
superior border. 
There Avere no other bones of Anser condoni in the collection, and I am inclined 
to belieA'e that that ponderous goose must have been Avell nigh extinct, Avhen the 
other anserine forms I have described above Avere flourishing in numlxTs. 
Mid-vertiail depth of mesial 
Anser 
Branta 
Anscr 
Ulor 
portion of os furcula given in | 
condoni. 
canadensis. 
albifrons. 
liiiccimitur. 
millimetres 
16 
8 ! 
■ . 
10 
Our Branta bernicla is a foot less in total length than its congener li. cana- 
densis, and Anser condoni must certainly have been twelve or fi)urtecn inches 
longer than Branta canadensis. 
I take pleasure in dedicating this extinct species to Professor Thoma.s Condon 
of the UniA’ersity of Oregon, the first naturalist Avho discovered and collected any ol 
the remains of fossil birds in the Silver Lake Kegion of Oregon.^ 
The specimens of the os furculaj of this goose are in Cope's collection : hpms 
Beds of Silver Lake, Oregon. 
Branta hypsibatus. 
This extinct Goose has already been described by Professor Coix', and 1 have 
examined the material upon Avhich he distinguished it.' 
Be-anta pkopinqua sp. nov. 
In describing his collection Professor Cope speaks of having discovered a (hKise 
that it contained, which upon comparison he found to come “ near nigricans .' I he 
fossil remains of the bird are Avell represented in the collection, and it imivos to lx* 
a small, true Brant Goose closely allied to nigricans. For it I propo.sc- the alx.vc 
name. 
iCope E D Bull. U. S. Geol. Siirv. Terr. IV, No. 2, 1878, p. 387. See also Kra,./a A. O. V. 
Code anfckL List of N. A. Birds, 1886, p. 364. Bra,Ua hyp.^Mes Coues MS. There w.u, but one bone of 
this bird found, a tarso-metatarsus, and probably it was not an abundant species. 
Ubid p. 389. 
