220 NORTH AMERICAN BIRDS. 



blotches were large and well marked ; in the others, less strongly traced, but 

 quite distinct. 



The nest was found in a tract of low land, covered with clumps of sedge, 

 on one of which it had been constructed. It is described as about the size 

 of a peck basket, circular, and composed entirely of small dry sticks, " fin- 

 ished off or topped out with small bunches of pine boughs." There was 

 very little depth to the nest, or not enough to cover the eggs from view in 

 takinii; a sicht across it. " No feathers were found in or about it. It was 

 simply made of small dry sticks, about six inches thick, with about one inch 

 of pine boughs for finishing oft' the nest." The eggs were found about the 

 20th of May. They contained young at least two weeks advanced, showing 

 that the bird began to lay in the latter part of April, and to sit upon her 

 eggs early in the following month. 



It will be thus seen that the eggs of this Hawk vary greatly in size and shape, 

 and in the presence or absence of marking, varying in length from 1.75 to 

 2.00 inches, and in breadth from 1.25 to 1.50, and in shape from an almost 

 gobular egg to an elongated oval. Some are wholly spotless, and others are 

 very strongly and generally blotched with well-defined purplish-brown. 



This Hawk was found breeding in the Humboldt Valley by Mr. C. S. 

 M'Carthy, on the Yellowstone by Mr. Hayden, at Fort Benton by Lieutenant 

 Mullan, at Fort Resolution by Mr. Kennicott, at Fort Rae and at Fort Simp- 

 son by Mr. Ross, at La Pierre House by Lockhart, and on the Lower Ander- 

 son by Mr. MacFarlane. 



Genus NISUS, Cuvier. 



Accipiter, Bris.s. 1760. (Type, Falco nisus, LiNN.) 



Nisiis, Cuv. 1799. (Same type.) 



Astur, Lacep. 1801. (Type, Falco palumharius, Linn.) 



Dcedolion, Savig. 1809. (Same type.) 



Dcedalium, Agas.s. (Same type.) 



Sparvius, Vieill. 1816. (Same type.) 



Jeraa;, Leach, 1816. (Same type.) 



Aster, Swains. 1837. (Same type.) 



Micronisus, Gray, 1840. (Type, Falco gahar, Daud.) 



Phabotypus, Glog. 181'2. (Same type.) 



Hieraspiza, 1844, Jcraspiza, 1851, and Teraspiza, 1867, Kaup. (Type, Falco tinus^ 



Latham. ) 

 Hieracosjnza, Agas. (Same type.) 

 Nimstur, Blas. 1844. (Same type.) 

 Urospiza, 1845, Urospizia, 1848, and Uraspiza, 1867, Kaup. (Type, Sparvius cirrhocepha- 



lus, Vieill.) 

 Leucospiza, Kaup, 1851. (Type, Falco novce-hollandice, Gmel.) 

 Cooperastur, Bonap. 1854. (Type, Acciiiiter cooperi, Bonap.) 

 Erythrospiza, Kaup, 1867. (Type, A. trinotatus TemuJ not of Bonap. 1830!) 



Gen. Char. Form slender, the tail long, the wings short and rounded, the feet slender, 

 the head small, and bill rather weak. Bill nearly as high through the base as the length 



