358 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



and fly low over the water. In feeding they dab at the surface to 

 pick out bits of succulent vegetation, which may be shaken to scatter 

 adhering water before they are swallowed. Often the head is com- 

 pletely immersed. They are local in occurrence compared to the more 

 widely distributed purple gallinule. 



The two subspecies present as breeding birds in the Isthmus differ 

 slightly in size, and in the extent and depth of brown coloration on 

 the back. 



Fig. 59. — Common gallinule, gallineta de agua, GaUimda chloropus. 



GALLINULA CHLOROPUS CACHINNANS Bangs 



Gallinula chloropus cachinnans Bangs, Proc. New England Zool. Qub, vol. 5, 

 May 17, 1915, p. 96. (Arbuckle Creek, De Soto County, Florida.) 



Gallinula chloropus caitralis Waldron DeWitt Miller and Ludlow Griscom, 

 Amer. Mus. Nov. no. 25, Dec. 7, 1921, p. 3. (12 miles south of Metapa, 

 central Nicaragua.) 



Characters. — Brown of back and wing coverts more extensive, 

 darker, and of a brighter shade, and spread over the greater wing 

 coverts, in some as a slight wash, but in many in an amount equal to 

 that found on the back. 



Measurements. — Males (16 from eastern United States and 

 Mexico), wing 167-181 (174.5), tail 64.0-86.0 (71.6), tarsus 49.0- 

 56.5 (52.7) mm. 



