318 FALCOXIDiE. 



the interscapulary region and lesser wiug-coverts deep velvety brown ; 

 upper tail-coverts white at their bases, shaded with grey and glossed 

 with greenish ; under wing-coverts and bases of inner secondaries 

 white ; bill dark horn-blue ; feet light milk-blue ; iiis rich dark 

 reddish brown. Total length 21 inches, culmen 1-3, wing 16-25, 

 tail to tip of outer rectrix 13-1, tarsus 1-4. 

 Uab. The same as that of the genus. 



a. Ad. st. S. America. Baron Laugier de Chartrouse. 



b, c. Ad. sk. Brazil. Lord Stuart de Eothsay [P.]. 

 d. Skeleton. Pm'chased. 



57. NAUCLERUS. ^^p^ 



Nauclerus, Vigors, Zool. Jmirn. ii. p. 386 (1825) N. riocouri. 



Clielictinia, Less. 1843 (teste Gray, uhi ?). 



Chelidopteryx, Kaup, Mm. Senckenh. iii. p. 258 (1845) N. riocouri. 



Cypselopteryx, Kaup, 1851 {teste Gray, ubi ?). 



Range. Western and Xorth-eastern Africa. 



1. Nauclerus riocouri. 



Elanoides riocouri, Vieill. et Oud. Gal. Oi's. i. p. 43, pi. 16 (c. 1823) ; 



BoiD). et Vieill. Enc. Meth. iii. p. 1206 (1823) ; Strickl. Orn. Syn. 



p. 142 (1855) ; Schl. Hamlb. Dierk. i. p. 107, pi. 1. fig. 5 (1857) ; 



id. 3Ius. P.-B. Milvi, p. 5 (1862) ; Heugl. Orn. N.O.-Afr. i. p. 102 



(1871). 

 Falco riocoui-i, Temm. PI. Col. i. pi. 85 (1824). 

 Elanus riocoui-i, Vig. Zool. Journ. i. p. 340 (1824). 

 Nauclerus riocomi," Vig. Zool. Journ. i. p. 386 (1825) ; Less. Traite, 



p. 73 (1831) ; Gray, Gen. S. i. p. 25 (1845) ; Bp. Comp. i. p. 22 



(1850) ; Hartl. Orn. W.-Afr. p. 11 (1857). 

 Nauclerus africanus, 8u). Classif. B. ii. p. 210 (1837). 

 Chelidopteryx riocourii, Kaup, Mus. Senckenb. iii. p. 258 (1845) ; id. 



Contr. Orn. 1850, p. 57. 

 MUvus riocouri, Giebel, Orn. Thes. p. 86 (1874). 



Adult. Above cinereous, interscapulary region and scapulars 

 slightly darker ; quills ashy grey, paler beneath, the feathers inclin- 

 ing to white at the base, especially on the inner web of secondaries, 

 which are white at their tips externaUy also ; tail-feathers externally 

 ashy grey, brownish on the inner web, the greater portion of which 

 from the base upwards is white ; forehead and indistinct eyebrow 

 whitish; cheeks, ear-coverts, sides of neck, and entire underparts 

 pure white ; the under wing-coverts with a broad patch of black 

 running down their whole extent parallel with the exterior margin ; 

 bill greenish dusky; feet yellow; iris red. Total length 14-5 inches, 

 culmen 0-65, wing 9-95, tail 7-8, tarsus 1-2. 



Hah. The same as that of the genus. 



a. Ad. St. W. Africa. Captain Sabine [P.]. 



b. Ad. sk, W. Africa. Captain Sabine [P.l. 



c. Ad. sk. Dakar, Senegal. M. A. Bouvier [P.J. 



