455 



ance, tlie tarsus being almost twice the middle toe in lengtli ; outer toe 

 longer than the inner ; posterior much the shortest. Claws normal, but 

 rather long, and only slightly curved. Tarsus with large scutelliB in 

 front, the lower four to six forming a single frontal row, continuous 

 with the scutellte of the top of the toes, the rest arranged in two paralle 

 series of alternating hexagonal, longitudinal scales ; those on the pos 

 terior face smaller, more nearly quadrate, and arranged in two longi 

 tudinal series. 



Species of Polyborus. 



CoioiON CHARACTERS. — Adult : Whole pileum, the body and wings 

 in general, and terminal zone of the tail dull black or dark brown. 

 Cheeks, neck, jugulum, tail-coverts, and tail dull white or light isabella- 

 color ; nape, interscapulars, and breast with transverse bars of the two 

 colors mixed; tail with narrow transverse bars of grayish. — Toung : 

 Black replaced by dull brown ; transverse bars of the neck and breast 

 replaced by longitudinal stripes. Tail similar. 



Species. 



A. — Eump and tail-coverts white, with or without bars; tail white, with 

 narrow bars of grayish-brown, and a terminal zone of black 2.00 

 inches or more wide. 



1. P. CHERIWAY. — Whole body and middle wing-coverts uniform 

 h]a:Ck {adult) or hvoww {young); tail-coverts without bars; ter- 

 minal zone of the tail about 2.50 wide. Wing, 14.60-16.50 ; tail, 

 8.80-10.00; culmen, 1.20-1.48; tarsus, 3.20-3.75; middle toe, 

 1.90-2.10. Hab. — Northern Tropical America, from Ecuador and 

 ilsrorthern Amazonia to southern border of the United States, 

 including the entire border from Southern California to Florida; 

 Cuba. 



2. P. THARUS. — Whole body and middle wing-coverts transversely 

 barred {adnlt) or striped {younq) ; tail-coverts barred; terminal 

 zone of tail about 2.00 wide. Win o-, 16.00-17.70; tail, 10.00-11.00; 

 culmen, 1.20-1.41; tarsus, 3.70-4.20; middle toe, 1.75-2.30. 

 Hah. — South America, from Amazonia southward. 



B. — Piump and tail-coverts light isabella-color, with broad brown bars; 

 tail light isabella-color, with broad bars of grayish-brown bordered 

 by zigzag, narrow bars of dusky; terminal zone less than 2.00 

 inches wide. 



3. P. LUTOsus.— Lower parts entirely light isabella-color, with 

 transverse bars {adult) or longitudinal stripes {young) of dark 

 brown, except on throat and cheeks; scapulars plain brown. 

 Terminal zone of tail, 1.00-1.60 wide; wing, 15.00-16.40; tail, 

 10.50-11.65; culmen, 1.25-1.35; tarsus, 3.50-3.75; middle toe, 

 1.80-2.10. JT«&.— Guadalupe Islands. 



POLYBOKUS THAEUS. 



SOUTHERN CARACARA. 



Falco thavm Mol. Sagg. St. Nat. Chile, 1782, 2G4.— Gm. S. N. i, 1788, 254.— Lath. Index 

 Orn. i, 1790, 16; Syn. Supp. ii, 18; Geu. Hist, i, 243.— Dald. Tr. Orn. ii, 

 1800, 41.— Shaw, Zool. vii, 1812, 170. 

 Folybonis tharm Strickl. Orn. Synon. i, 1855, 19 (part). — Gurxey, Cat. Eapt. 

 Norw. Mns. 1884, 17.— SCL. & Sal v. Ibis, iv, 1868, 187 (Gregory Bay, Str. Ma- 

 gellan, May-Feb.); P. Z. S. 1869, 2.52 (Maruria, Venezuela); ib. 634 (Conclii- 

 tas, Resp. Argent.); Nomencl. Neotr. 1873, 123.— Gray, Hand List, 1, 1869. 17. — 

 EiGW. Pr. A. N. S. Pbilad. 1870, 145 ; .Pr. Boston Soc. May, 1873, — ; in'B. B. 

 & R. Hist. N. Am. B. iii, 1874, 177 (foot-note).— Hudson, P. Z. S. 1872, 534 

 (Rio Negro, Patagonia). — Sharpe, Cat. Ace. Br. Mus. 1874, 31. 



