453 



3. MiLVAGO. — Tooth andaotch of the tomia of the bill distiuctly 

 indicated ; lower jaw normally feathered ; outer toe decidedly 

 longer than the inner ; posterior toe not reaching the first 

 joint of the middle toe; claws sharp, strongly curved (as in 

 the Falcoyies); posterior face of the tarsus with, two distinct 

 rows of quadrate scales. Upper tail-coverts normal, covering 

 about one-third the tail ; size small. 



B. — Tarsus scarcely longer than the middle toe; outer toe very much 

 longer than the inner, which is but little longer than the posterior 

 one. Inner webs of primaries shallowly sinuated. Habits strictly 

 arboreal. 



4. Ibycter, — Nostril circular, near the middle of the cere, its 

 tubercle either concealed or exposed : anterior outline of the 

 cere doubly curved. Tarsus without transverse scutellae 

 either in front or behind. 



GeograpJdcal distribution. 



The Polyhori are most numerous in South America, only four of the 

 eleven known species being found north of Panama; and of these, one 

 {Milvago chimachivia) finds its northern limit in Veragua, while another 

 {Ibycter americani(s) extends no farther northward than Guatemala and 

 Honduras. The remaining two extend northward only to the limits of 

 the subtropical country, or to about latitude 30° ; Folyhorus clieriivay 

 being more or less abundant along the southern border of the United 

 States, from Southern California to Florida, as well as throughout Mid- 

 dle America, thence southward, and also on the islands of Socorro and 

 Tres Marias, off the western coast of Mexico, and in Cuba; P. lutosus 

 is restricted to the Guadalupe Islands, off the coast of Lower California, 

 between latitude 28° 45' and 29° 10' north. In South America, the range 

 of the group is much more extensive, every portion of the continent, 

 even to its extreme southern limits, being inhabited by one or more 

 of the species. According to the distribution of these birds, the region 

 inhabited by them may be divided into the following '•'provinces" and 

 "districts." 



A. — ISToRTHERN Province — embracing the whole of Middle America 

 north to about 30°, and also that portion of South America comprised by 

 the states of Ecuador, New Granada, Venezuela, and Guiana, and the 

 northern drainage of the Amazon. It comprises — " 



a. Continental District, including the whole excepting the Guadalupe 

 Islands; and 



h. Guadalupe District, embracing the islands of Guadalupe alone. 



B. — Southern Province — embracing all of South America south of 

 the Amazon and Ecuador. It comprises — 



a. Atlantic District, or the entire area drained by the rivers flowing 

 into the Atlantic; 



h. Magellan District, or the country adjacent to the Straits of Ma- 

 gellan, embracing Tierra del Fuego, Falkland Islands, and the eastern 

 slope of Patagonia ; 



c. Southern Pacific District, or the narrow Pacific slope, from Pata- 

 gonia northward to Peru ; and 



d. northern Pacific District, a continuation of the former northward 

 to Colombia. 



According to this arrangement, the species are distributed as follows: 



