524 OPISTH0COMID.15. 



1st primary miich shorter than the 2nd, which is shorter than 

 the 10th ; 6th-8th subequal and longest. Fifth cubital remex 

 present. 



Tarsus reticulated, shorter than the middle toe and claw. 



An elongate crest of rather stitf-shafted feathers. 



Sides of the head mostly naked. 



Sexes similar. 



Range. S. America : Surinam to the United States of Colombia 

 and southwards to Bolivia. 



1. Opisthocomus hoazin. 



Crax fuscus mexicanus, Briss. Oni. i. p. 304 (1760). 



Faison huppe de Cayenne, d'Auhent. PL Enl. ii. pi. 38 [no. 337]. 



L'Hoazin, Buff. Hist. Nat. Ois. ii. p. 385 (1771). 



Phasianus hoazin, Miill. 8. N. Suppl. p. 12.5 (1770). 



Crested Pheasant, Lath. Gen. Syn. ii. pt. ii. p. 720, pi. Ixiv. (1783). 



Phasianus cristatus, Gm. S. N. i. pt. ii. p. 741 (1788) ; Lath, Ind. 

 Orn. ii. p. C31 (1790). 



Orthocorys cristata, Vieill. Analyse, p. 49 (1816). 



Opisthocomus hoatzin, Steph. in Shaiu's Gen. Zool. xi. p. 193 (1819) ; 

 Graij, Hand-l. B. ii. p. 126 (1870). 



Sasa cristata, Vieill. ISouv. Diet. d'Hist. Nat. xxx. p. 216 (1819) ; id. 

 Gal. Ois. 1. pt. ii. p. 32.5, pi. 193 (J 825). 



Opisthocomus cristatus, L'Hernnnier, C. R. v. p. 433 (1837) ; Gray, 

 Gen. B. ii. p. 396, pi. xcvii. iig. 4, pi. xcviii. (1845) ; Schomburyk, 

 Reise Brit. Guiana, iii. p. 712 (1848); Burmeister, Syst. Uebers. 

 in. p. 342 (1856) ; Sclat. P. Z. 8. 1857, p. 10 [Bogota] ; Huxley, 

 P. Z. S. 1867, pp. 435, 460, 1868, p. 304 [skeleton] ; Neiuton, Ibis, 

 1869, p. 217; Cabanis, J. f. O. 1870, p. 318, pi. i. tig. 3 [jt^^V, 

 Sclat. Sf Salvin, P. Z. S. 1873, p. 308 [Cashihoya, E. Peru]; 

 Perrin, P. Z. S. 1873, p. 685 [Maroni P., Surinam] ; id. Trans. 

 Z. S. ix. p. 353, pis. 63-66 (1875); Broivn, Canoe and Camp- 

 life Brit. Guiana, p. 257 (1876) ; Sachs, Schild. Reise nach Vene- 

 zuela, p. 259 (1878) [Confluents of the Orinoco] ; Garrod, P. Z. S. 

 1879, p. 109 [anatomy] ; Forbes, Ibis, 1881, p. 25 ; Sclat. P. Z. S. 

 1881, p. 2.59 [eggs from Obidos, Amazons] ; Nathusius, J. f. 0. 

 1881, p. 334, 1882. p. 275 ; Berlejysch, Ibis, 1884, p. 440 [Angostura, 

 Venezuela, and Yquitos] ; Briyhain, Chicago Ac. Sci. p. — (1884) 

 [Marajo I., Anabiju R.]; id. Ibis, 1885, p. 118; Tacz. Orn.Perou, 

 iii. p. 262 (1&861 [Casiuboya] ; Hurting, Ibis, 1886, p. 98 ; W. L. 

 Sclater, Ibis, 1887, p. 319 ["Berbice Pi., Brit. Guiana] ; Quelch, Ibis, 

 1888, p. 378 [Berbice R., Brit. Guiana] ; id. Timehri, ii. p. 363 

 (1888) [Abary Creek] ; Young, Notes Leyd. Mus. x. p. 169, pi. 8 

 (1888) ; Beddard, Ibis, 1889, pp. 283-293 [anatomy] ; Newton, 

 Ibis, 1889, p. 577; Allen, Bull. Am. Mus. N. H. ii. pi 107 (1889) 

 [Lower Beni, Bolivia] ; Sclat. P. Z. S. 1889, \>. 57 ; Quelch, Ibis, 

 1890, p. 327 [Abary Creek and Berbice P., Brit. Guiana, habits] ; 

 Parker, P. Z. S. 1890, p. 44 ; id. Trans. Zool. Son. xiii. pp. 43-86, 

 pis. yii.-x. (1891) ; Gadow, P. R. Irish Ac. (3) ii. p. 147, pis. yii. 

 & viii. (1892). 



Adult male and female. General colour of the upper parts dark 

 brown glossed with oUve ; top of the head covered with long, narrow, 



