90 NEW YORK STATE MUSEUM 



complete [Xat. M-us. spec. no. 18444] to show that the vertically 

 shallow, perforate septum narium does not come in contact with 

 the spongy portions of the maxillo palatines, nor do the latter 

 come in contact with each other. 1 The superior portions of the 

 lacrymals are long, moderately slender, and probably do not sup- 

 port accessory pieces at their ends. Below, the descending part of 

 a lacrymal is somewhat expanded in a transverse direction, and 

 shows a large pneumatic foramen on its anterior surface. The 

 mandible is notably slender. 



The lower arc of its U-shaped os furcula is compressed to be 

 thin and platelike in the transverse direction, and there is no hypo- 

 cleidium. Above, the free clavicular ends are much as we found 

 them in Elanoides, having in each case an outside shoulder to fit 

 upon the corresponding coracoid, and the apex reaching back to 

 touch either scapula. A coracoid, although practically agreeing in 

 form with that bone as we have found it in other Falcones already 

 examined, is peculiar only in being more slenderly fashioned, and in 

 having its perforating foramen high up on the scapular process. A 

 scapula is narrower than in either Elanoides or Circus. The entire 

 girdle is pneumatic. 



Elanus has a sternum different from any of the Falconidae thus 

 far examined. Its keel is very short anteroposteriorly, leaving upon 

 the ventral aspect of the xiphoidal portion a comparatively broad and 

 smooth emargination. It is this surface that the inferior border of 

 the carina widens out upon, a distinct line being carried transversely, 

 on either side, to the lateral edge of the body of the sternum. Just 

 beyond this line the sternum exhibits an elliptical foramen, one on 

 either side, and well out toward its lateral border. There are five 

 facets on either costal margin, and the coracoidal grooves slightly 

 decussate behind the small manubrium. Posteriorly, the free 

 xiphoidal margin itself is regularly scalloped, there being a small 

 median notch, and a long, shallow one outside of it, on either hand. 

 Elanus axillaris has a sternum much like the one I have 

 just described for E . leucurus. My material does not offer 

 either the femur or the tibiotarsus in the pelvic limb, but the tarso- 

 mctatarsus and foot are at hand, both of which present points of 

 interest. The first mentioned has somewhat the form that it has 

 in Elanoides, but the hypotarsus is represented by two processes 

 with a wide open valley between them: and the joints of the fourth 



1 I am inclined to believe that in the future, specimens of skulls from adult indi- 

 viduals of this kite will be met with, that will prove to be exceptions to Professor 

 Huxley's definition of desmognathism, as it occurs among birds. 



