430 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



The present subspecies is characterized by the prevalence of bhick 

 and gray above, and in worn breeding dress appears very black in- 

 deed, especially on the rump. Skins from Uruguay are similar to 

 those from Buenos Aires, but those from Rio Grande do Sul verge 

 toward hunieralis as they are more brownish above. A good series 

 from Avia Terai and General Pinedo, in central and western Chaco, 

 are intermediate between dor^^ialis and tucumnnerisis as is to be ex- 

 pected. Some, in fact, appear identical with tucumanensis^ others 

 resemble dorsalis, and others are halfway between. 



A puzzling circumstance is that a specimen labelled Puerto 

 Pinasco, September 4, 1916, taken by Cherrie, is typical of dorsalis, 

 while another that I secured at the same point September 3, 1920, 

 is as typical of the broAvn-backed hiniieralis from Brazil and north- 

 ward. Further specimens alone can solve the riddle presented, espe- 

 cially since huineralis is the form also from Sapucay, not far from 

 Asuncion, Paraguay. 



M. dorsalis is the best marked of the forms of the species. 



5. MYOSPIZA HUMERALIS TUCUMANENSIS Bangs and Penard. 



Myospiza humeralis tucunianensis Bangs and Penard, Bull. Mus. Conip. 

 Zool., vol. 62, April, 1918, p. 92. (Tapia, Tucuman.) 



Similar to dorsalis but paler above with dark central markings 

 of feathers narrow, with a buffy-brown cast to upper surface. De- 

 cidedly paler and grayer above than humeralis. 



Specimens seen from Tapia, Tucuman (the type specimen, col- 

 lected by Dinelli) and Victorica, Pampa. A few skins taken by 

 Miller and Boyle at the end of April and the beginning of May at 

 Avia Terai and General Pinedo, Chaco, are closely similar to the 

 type and may possibly be migrant individuals of this form, though 

 taken at the same time as birds representative of dorsalis. 



The only specimen of M. h. humeralis that I secured was an adult 

 male taken September 3, 1920, at Puerto Pinasco, Paraguay, near 

 the E.io Paraguay. On this date the birds were common in open, 

 grassy localities, and one little colony, established in an area of 

 bunch grass near the river, was about ready to breed. Males sang, 

 from weeds or fence posts, a low ditty that may be represented as 

 chip-f-p chee-ee-ee-ee chee chee in the cadence and tone of a song 

 sparrow {Melos'piza melodia). Their call note was a faint tsif. 

 On the ground, they ran rapidly ahead of me from cover to cover, 

 or flushed wuth an undulating flight. As no others were taken those 

 recorded at Kilometer 80, September 9 to 20, and Kilometer 200, 

 September 25, west of Puerto Pinasco, are assigned here with reser- 

 vation. 



The single male preserved is absolutely typical of the reddish 

 brown northern form. 



