1888.] PROCEEDINGS OP UNITED STATES NATIONAL MUSEUM. 249 



but much shorter than iu Ducks and Geese generally. We note here 

 also that a partial septum narium is present, which is absent in Mergus 

 and not a constant character among the others. 



Fig. 27. Skull of Branta canadensis hutehinsii; right lateral view ; life size. From a specimen in the 



author's collection. 



The lacrymal has the broad descending process, but not so enor- 

 mously expanded as we find it iu the Swaus and in GJaucionetta. It 

 will also be noted how this tends to approach the sphenotic process of 

 the opposite side of the orbit, which it nearly succeeds in meeting in 

 the Golden Eye. 



Agaiu, the condition of the iuterorbital septum as it is generally 

 formed among the Ducks and Geese is well exemplified in this Goose, 

 Fenestra} occur in the region of the exit of the first pair of nerves, but 

 the center of the plate is impervious. Attention is invited, too, to the 

 form of the palatine, quadrate, and pterygoid on this lateral view. 



The crotaphyte fossa is small and inconspicuous, and confined entirely 

 to the side of the head. As in all Anatidce, the entrance to the auricular 

 chamber is thoroughly walled about with bone, without presenting any 

 flaring wing-like extensions as we sometimes see in birds. 



The unusual size of the brain-case in Hutchin's Goose is, perhaps, 

 better appreciated upon a direct posterior view than it is here on our 

 lateral one. Comparatively speaking, it is far above, I think, the 

 average for a bird of its size. 



Still regarding this skull from the aspect presented, and to make 

 some of its characters still more evident by contrast, we will place it 

 bcskle the skull of Mergus, already described above. We note the 

 difference in the form of the bill; the presence of the craniofacial line 

 in the Goose, while it is absent in the Merganser. Both have the nar- 

 row depressions along the margins of the orbits for the nasal glands, 

 but posterior to this the Goose has the dome like vault of the cranium 

 so characteristic of the more highly organized types of the Anatidce, 

 while we see that this region in the Merganser is much flattened. 



Regarding the skull from the under side, we are particularly to note 

 the difference in form of the maxillo palatines, the palatine bodies, and 

 the pterygoids. 



