46 Proceedings of the Biological Society of Washington. 



Measurements (in millimeters). — Males (2 specimens), wing 94.5-96.0, 

 tail 87.0-91.5, culmen 19.0-21.0, depth of bill from posterior end of gonys 

 to highest point of culmen 13.5-14.5, tarsus 27.8-28.5. 



Females (2 specimens), wing 91.5-93.5', tail 82.4-89', culmen 19.3-20'. 

 depth of bill from posterior end of gonys to highest point of culmen 13.5- 

 14', tarsus 26.7^. 



Range. — Province of Mendoza (Alto Verde, Potrerillos, and Mendoza), 

 and western Gobernaci6n de Pampa (Victorica). 



Remarks. — This form, characterized by large heavy bill, may be expected 

 to range through the semi-arid regions of San Luis and San Juan in addition 

 to the geographic distribution indicated by specimens at hand. In sepa- 

 rating it we have had available skins of the smaller billed, somewhat 

 brighter colored, eastern form from Paraguay (type locality) and Tucumdn, 

 Formosa, Chaco, Corrientes and Entre Rios, Argentina. In males of S. a. 

 aurantiirostris as here restricted the culmen measures from 17.4 mm. to 

 18.4 mm. (average 17.8 mm.) and the depth of bill, measured from the 

 posterior end of the gonys to the highest point of the culmen 11.2 mm. 

 to 11.9 mm. (average 11.6 mm.). A female (from Las Palmas, Chaco) 

 measures as follows: wing 90.0 mm., tail 85.6 mm., culmen 17.5 mm., 

 depth of bill (taken as described above) 11.6 mm., tarsus 26.5 mm. The 

 bill in three other female birds (from Entre Rios, and Tapia, Tucumdn) 

 has the following dimensions: culmen 17-18 mm., depth (taken as in others) 

 11.7-12.7 mm. 



1 Measurement of type specimen. 

 20ne specimen. 



