FAMILY ANHINGIDAE 69 



flying down the Rio Mamoni, near its mouth at Chepo, a bird near 

 the center of one flock carried a good-sized twig in its bill, while 

 maintaining its proper place in the long line of its companions, 

 indication that the nesting season was near. 



According to Bent (U. S. Nat. Mus. Bull. 121, 1922, pp. 262-263) 

 4 or 5 eggs constitute the normal set. These have a ground color of 

 bluish white concealed beneath a coating of chalky white. In addi- 

 tion usually they are much nest-stained. Measurements range from 

 47.5-58x29-37 mm. 



In Venezuela these birds are known as the cotua. 



Family ANHINGIDAE : Snakebirds ; Cuervos de Aguja 



The four species recognized in this family are found throughout 

 the warmer areas of the world, mainly on fresh water. All are 

 similar in slender form, with long, straight bill (in which the edges 

 of the mandibles are finely serrate), narrow head, long, slender 

 neck, and narrow body. Some ornithologists have united this family 

 with the cormorants, presumably on the basis of general resem- 

 blances in color and manner of life, but anatomical studies show 

 differences too important to warrant this combination. Among the 

 distinctions, the snakebirds have a peculiar stomach in which there 

 is a separate small lobe at the upper end for the glands found in 

 most other birds in the proventriculus, and a second division at the 

 lower end, in which a series of slender, hairlike processes are 

 clustered around the narrow opening into the intestine. There is also 

 an arrangement in the upperpart of the neck that serves as a trigger 

 to control the head as a spear to impale the fish that form the food. 

 These are peculiar adjustments not found in cormorants, and with 

 other details establish separate family status. It may be noted also 

 that in the snakebirds primaries and secondaries are molted simul- 

 taneously as they are in ducks, and so for a period the birds are 

 flightless. 



ANHINGA ANHINGA LEUCOGASTER (VieiUot): Anhinga; Cuervo de Aguja 



Figure 13 



Plotus leucogaster Vieillot, Nouv. Diet. Hist. Nat., nouv. ed., vol. 1, Sept. 1816, 

 p. 545. (Florida.) 



Long neck, with slender head and long straight bill mark this 

 species, as compared to the cormorant. 



Description. — Length 760 to 900 mm. Very slender in form with 



