FAMILY NYCTIBIIDAE I9I 



browner, less gray, with reduced vermiculation of dusky on the back, 

 and the sides of the crown extensively white, flecked with dusky, 

 forming a broad band above each eye. The measurements of 402 mm. 

 in the wing of both, and of 277 and 282 in the tail indicate the large 

 size. 



The typical race ranges from Lake Nicaragua, Nicaragua (speci- 

 men in British Museum taken March 24, 1896) and from Panama 

 through South America to Peru and southern Brazil. The species has 

 not been reported to date from Costa Rica. 



NYCTIBIUS GRISEUS PANAMENSIS Ridgway: 

 Lesser Potoo; Urutau 



Figure 31 



Nyctibius griseus panamensis Ridgway, Proc. Biol. Soc. Washington, vol. 25, 

 May 4, 1912, p. 91. (Nata, Code, Panama.) 



A nocturnal species, goatsuckerlike in form, but with longer tail 

 and wing ; like the great potoo, but less than half as large. 



Description. — Length 340-380 mm. Two color phases, one gray, 

 the other much darker, blacker, more cinnamon-brown; male and 

 female alike. Adult, gray phase, crown and hindneck sooty black, with 

 the feathers bordered with white ; back, scapulars, and rump grayish 

 brown, streaked indefinitely with black, somewhat mottled with dusky 

 brown, buff, and white, and spotted with black; lesser wing coverts 

 black ; middle coverts clay color and white, mottled with dusky, and 

 streaked with black ; greater coverts and primaries sooty black, spotted 

 and barred indistinctly with grayish white; outer secondaries barred 

 and mottled with white ; tail dull black, barred indistinctly with gray 

 and grayish white ; throat white edged and mottled with black, buff 

 and gray; upper breast brownish gray, mottled with dull white, with 

 black shaft streaks, and a black necklace of heavy spots ; lower breast, 

 abdomen, and under tail coverts white, mottled lightly with gray and 

 buff, with shaft streaks of buff ; edge of wing white ; under wing 

 coverts blackish slate spotted with black. 



Dark phase: much darker throughout, with black, dark gray, and 

 dull cinnamon predominant ; wings much blacker. 



Young, heavily covered with downy feathers that are predominantly 

 pure white with shaft lines of black above and below ; a wash of pink- 

 ish buff on back and, more lightly, on lower surface; lesser wing 

 coverts and growing quills black. 



Iris yellow ; bill fuscous-black, with the cutting edge, including the 



