5. PLECTROPTERUS. 47 



3. A South-eastern African race (P. ni[/er), of a very large size ; 

 the adult (?) male has scarcely any frontal knob, the throat and 

 under tail-coverts mostly black, the sides also extensively black, and 

 no caruncles on the naked forehead. 



4. A Shoan race {P. scioamis) ; the adult male (?) is similar to 

 that of P. niger, but has the naked skin of the forehead covered 

 with many caruncles. 



Key to the Species. 



a. Throat and under tail-coverts white ; abdomen 



broadly white ; adult males with a distinct 



frontal knob, and bare rhomboidal spaces on the 



sides of the neck. 

 a'. Frontal knob very prominent in adult males. . riipjjelU, p. 47. 

 b'. Frontal Iniob smaller in adult males gambensis, p. 48. 



b. Throat and under tail-coverts mostly black ; the 



white on the abdomen much reduced, the 

 black on the sides being much extended ; size 

 very large, 

 c'. Adult males with a small frontal knob ; many 



caruncles on the naked skin of the forehead. . scioamis, p. 51. 

 d'. Adult males with scarcely any frontal knob, 

 and with no caruncles on the naked skin of 

 the forehead niger, p. 50. 



1. Plectropterus rlippelli. 



Cygnus gambensis, Rilpp. (nee Linn.) Mus. Senckenb. iii. p. 12 t. 1 

 (1839); Schleg. Dierent. p. 277 (1804). 



Plecti'opterus gambensis, Childr. {nee Linn.) in Denh. Sf Clappert. 

 Trav. ii. App. p. 204 (1826) ; Riipj). Syst. Uebers. p. 1.37, n. 485 

 (1845) (Abyssinia and Sennaar); Rchnb. Syn. Av., Natatores, 

 t. 110. f. 984 {e.v Riippell) (1845) ; Vierth. Nanmannia, 1852, 

 pp. 40, 41, 42 ; Brehm, J. f. O. 1854, p. 84 (Sudan) ; Hartl. ibid. 

 p. 302 (part.); BreJmi, Vogelf. p. 365 (1855); Heuc/I. Uebers. 

 n. 680 (1856) ; Hartl. Syst. Orn. Westafr. p. 246, n. 697 (part.) 

 (1857) ; Brehm, J. f. O. 1857, p. 378 (N.E. Afr.), 1858, pp. 4U9, 

 410, 471 ; Heuf/l. J. f. O. 1863, pp. 4, 164 ; Antin. Cat. Desrr. 

 p. 112 (1864) ; 'Schleg. Mus. P.-B., Anseres, p. 93 (part.) (1866) ; 

 Jleiic/L Reise Abess. 1861-62, p. 28S (1868) ; id. Reis. in d. Geb. 

 Weiss. Nil, 1862-64, pp. 133, 384 (1869); id. Petenn. Geogr. 

 Mifth. 1869, p. 413. 



Anser (Plecti-opterus) gambensis, Brehm, J. f. O. 1853, Extrah. 

 p. 104 (N.E. Africa), 1855, pp. 486, 488, 1856, p. 468. 



? Plectropterus brevirostris, Brehm, Vogelf. p. 365 (1855). 



Plectropterus riippelli, Sclat. P. Z. -V. 1859, p. 132, pi. 153. f. 1, 



1860, pp. 28-42 (with cut of the head and trachea) ; Hartl. J. f. O. 



1861, p. 272 ; Ryt. Syn. Anat. p. 24 (1869) ; Finsch cV Hartl. 

 V6(/. Ost-Afr. p. 801 (part.) (1870) ; G. R. Gr. Hand-list, iii. 

 p. 73, n. 10554 (1871) ; Sclat. P. Z. S. 1876, p. 696 (Zool. Gai-d.), 

 1877, p. 48, 1880, p. 498; Rchmc. Viig. d. Zool. Giirt. p. 68 

 (1882) ; Sclat. List Vert. An. 8th ed. p. 415, n. 942 (E. Africa) 

 (1883) ; Hartert, Kat. Vogelsamml. p. 226, n. 3352 (Abyssinia) 

 (1891). 



