102 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



grounds. Four specimens that I secured have the following char- 

 acteristics : An adult male shot at Victorica, Pampa, on December 

 28, 1920, a breeding bird, has the tip of the tail mixed rufous and 

 white, the black subterminal band 12 mm. wide at its widest point, 

 the inner web of the outer rectrix rufescent, unmarked save for the 

 subterminal bar, and the following measurements : Wing, 186 ; tail, 

 128 mm. It thus has the color markings of cintiamoTnina, but is 

 smaller than most of that form. A female taken at Guamini, Buenos 

 Aires, March 8, 1921, has the black tail bands interrupted centrally, 

 very slightly restricted, and the following measurements: Wing, 

 197.5; tail, 130.5 mm. It is within the limit of measurement for 

 cinnamomina, but is more boldly marked. An adult male shot at 

 Las Palmas, Chaco, July 27, 1920, has the tips of the tail without 

 rufous, the subterminal band 16-17 mm. wide, the outer rectrix 

 with the inner web partly white, with one black spot in addition 

 to the subterminal band, the wing 190 and the tail 128 mm. The 

 bird thus slightly approaches australis in coloration, but is large. 

 An adult breeding male from San Vicente, in eastern Uruguay, taken 

 January 25, 1921, has the tip of the tail rufous, the subterminal 

 band 16 mm. wide, the external rectrix with two bars on the white 

 and rufous inner web, the wing 189 and the tail 123 mm. This bird 

 from its geographic position might be supposed to be near australis^ 

 but seems as near cinnamomina as the others. From the review 

 above it will be seen that these specimens are all more or less inter- 

 mediate, but I have considered them all nearer cinnamomina than 

 atis trails. 



The sparrow hawk was recorded as follows : Las Palmas, Chaco, 

 July 16 to August 1, 1920 ; Riacho Pilaga, Formosa, August 21 ; For- 

 mosa, Formosa, August 23 and 24; Puerto Pinasco, Paraguay, Sep- 

 tember 1 to 20 ; General Roca, Rio Negro, November 23 and 27 ; Vic- 

 torica, Pampa, December 24 to 29; La Paloma, Uruguay, January 23, 

 1921; San Vicente, Uruguay, January 25 to February 2; Lazcano, 

 Uruguay, February 5 to 9; Rio Negro, Uruguay, February 17 and 

 18; Guamini, Buenos Aires, March 3 to 8; Mendoza, Mendoza, 

 March 13; Potrerillos, Mendoza, March 16 to 21; Tunuyan, Men- 

 ■ doza, March 23 to 29 ; Tapia, Tucuman, April 6 to 13. 



Wherever found the bird was recorded as a watchful observer 

 from some commanding perch from which it had a clear outlook 

 over open country. In the breeding season it circled about scream- 

 ing killy hilly hilly., but at other seasons it was silent, only taking 

 wing when too closely pressed. Occasionally in the Chaco I saw one 

 stooping swiftly at some inoffensive Ileterospizlas at rest in a tree 

 top that perhaps had roused the ire of the smaller bird through the 

 usurpation of a favored perch. At Kilometer 80, near Puerto Pi- 

 nasco, sparrow hawks seemed to be nesting on September 7, but in 



