VO 'i909^ VI ] Towxsend, Use of Wings and Feet by Diving Birds. 235 



imbedded in muscular tissue, while the tibia is long and provided 

 with a crest or keel on the anterior surface of the proximal end, 

 to which the powerful muscles that move the tarsus and toes are 

 attached. In the Grebes there is a very large patella. In these 

 respects this group resembles the fossil Hesperornis, a toothed bird 

 with wings represented by mere vestiges, but one that was strongly 

 specialized for propulsion through the water by means of the feet 

 alone. 



The Loon and the Red-throated Loon in diving keep the wings 

 closely pressed to the sides, and disappear below the surface without 

 a splash, propelled apparently by the leg action alone. I have 

 not been able to see these shy birds under water, but the inference 

 that they do not use their wings there is confirmed by Mr. C. H. 

 Townsend (25) who says in regard to a tame Loon observed in the 

 New York Aquarium: "In exploring the bottom of the pool, or in 

 pursuit of Killifishes it swam under water with its tvings closely 

 folded — never in use." The italics are his. The pool in which 

 the Loon was confined was of ample size to display the agility of 

 both bird and fish; it was twenty-eight feet long and three feet 

 deep. Evans (3) states positively both of Loons and Grebes that 

 "when submerged they do not use the pinions." C. Lloyd Morgan 

 (27) says: "It must be remembered that Grebes and divers do not 

 use the wings for progression under water." Lea (8) says of the 

 Loon: "It uses its large webbed feet only, when swimming [under 

 water]." 



Although progression by the feei alone seems to be the rule in 

 this group, yet it is a fact that at times the wings also are used. 

 Thus Mr. C. Wm. Beebe, whose opportunities at the New York 

 Zoological Park are unusually great, writes me under date of Nov. 6, 

 1908, that "Grebes and Loons do [use their wings] at times of 

 emergency to turn quickly, or get up a burst of speed." 



Mr. Wm. Brewster tells me, and the observation has been con- 

 firmed by others, that Loons in diving under boats to avoid being 

 hemmed in, or in hurrying from their nests, use their wings as well 

 as their feet, and this I think has given rise to the idea that they 

 always use their wings. I have also been told by those who have 

 observed young Loons, that they use both wings and feet in diving. 

 A note of this sort was given me by Mr. F. H. Allen, who was im- 

 pressed by the "quadropedal action" of the young bird under water. 



