FAMILY COCHLEARIIDAE II5 



of the three races recognized are covered in the present report, a 

 very pale one of South America that ranges from southwestern 

 Darien southward, and a very dark one, found in southwestern Costa 

 Rica and most of Panama, that enters Colombia on the northwestern 

 shores of the Gulf of Uraba. The third, Cochlearius cochlearius 

 zeledoni (Ridgway), of Mexico and most of Central America, is 

 paler gray above than C. c. panamensis of Panama, but otherwise 

 is similar. These birds suggest night herons in general appearance 

 but are marked at once by the broad bill — less than twice as long 

 as it is wide — from which the family takes its name. In the adult a 

 crest of broad, loose feathers extends a third of the way down the 

 neck and the dorsal feathers are elongated to the level of the 

 rump. 



The characters that set these birds off as a distinct family com- 

 pared to the true herons (Ardeidae) are found in the enlarged bill, 

 which is a scoop instead of a spear, and in the considerable struc- 

 tural changes in the mouth and skull that accompany this. There 

 are four pairs of powder-down patches instead of the three of true 

 herons. The bill at hatching is short, triangular, broad at the base, 

 and tapers rapidly to a blunt point, an appearance quite different 

 from that of true herons of the same age. A downy specimen of 

 this age of the race Cochlearius cochlearius zeledoni from southern 

 Veracruz, with an tgg tooth present on both maxilla and mandible 

 is dull white below, pale gray above, and brownish black on the 

 crown. 



COCHLEARIUS COCHLEARIUS (Linnaeus): Boat-biUed Heron; 

 Garzota Cuchara 



Figure 19 



A heronlike bird of medium size, with a heavy bill in which the 

 breadth is more than half the length. 



Description. — Length 480 to 510 mm. Adult, forehead and fore- 

 crown white; rest of crown, broad, elongated nuchal plumes, and 

 a patch on upper back, blackish slate; rest of upper surface, in- 

 cluding sides of neck, gray ; breast, abdomen, and under tail coverts, 

 cinnamon-brown ; sides and flanks slaty black. 



As stated under the family heading, this species suggests the night 

 herons in general, though distinct from them in many ways. During 

 the day boatbills remain in roosts in mangrove swamps, or in inland 

 localities, in trees over small streams or ponds. They fly readily when 

 approached, but usually merely to heavier cover nearby. Though 



