464 NORTH AMERICAN BIRDS. 



The male bird is very pugnacious, and was observed to attack and drive 

 away an Accipiter fuscus, the Hawk retreating as rapidly as possible. When 

 the nest is approached, the male often rises high into the air and then sweeps 

 down almost to the head of the intruder, its swift descent being accompa- 

 nied by a very j^eculiar shrill, screeching buzz, of an extraordinary degree 

 of loudness to be produced by so small a creature. The same sound Mr. 

 Hidgway noticed when the bird was passing overhead, in a manner not ob- 

 served in any other species, its horizontal flight being by a peculiar undu- 

 lating course. The shrill noise made by the male of this species he suggests 

 may be caused by the curious attenuated and stiffened outer primary. He 

 noticed a curious piece of ingenuity in nest-making on the part of this species. 

 The nest in question was fastened upon a dead twig of a small cottonwood- 

 tree ; the loosening bark, which probably had separated after the nest was 

 finished, had allowed the nest to turn around so as to hang beneath the 

 branch, thus spilling the eggs upon the ground. The owners, however, built 

 another nest upon the top of the branch, fastening its sides to that of the 

 old one, and making the new nest lighter and less bulky, so that the weight 

 of the older nest kept the other in a permanently upright position. 



Genus ATTHIS, Reichenbach. 



Atthis, Reich. Cab. Jour. f. Orn. extraheft fiir 1853, 1854. Appendix B. (Type, Ornys- 

 mya heloisa, Lesson, Del.) 



Gen. Char. Size very diminutive ; bill short, scarcely longer than the head. Outer 

 primary attenuated nearly as in Selasphorus ; the tail graduated, the feathers, however, 



not lanceolate-acute, but rounded at end, and tipped with 

 white in the male. 



This genus seems closely related to Selaspho- 

 rus, agreeing in character of throat, the curious 

 attenuation of outer primary, and the general 

 shape of the tail, with its rufous base and edg- 

 ing. The feathers, however, are not lanceolate 

 and pointed, either sharply as in S. rufus, or ob- 

 tusely as in platycercus, but are more equal to near the end, where they round 

 off. The white tip of the tail in the male seems to be the principal reason 

 why Mr. Gould removes the single species from Selasphorus, where it was 

 previously placed by him, and where perhaps it might have not inappropri- 

 ately remained. 



Atthis heloisa. 



