170 RIVER AND POND DUCKS 



reaching fullest development in the latest migrants the so-called Red- 

 legs, (e) They point out that the soft parts (bills and feet) of many ducks 

 show seasonal changes of colour and changes of colour due to age. (f) 

 The white tips of the greater coverts, the generally heavier feathering, 

 the greater average weight, points which are characteristic of the Red- 

 leg, they claim are nothing more than indications of maturity, (g) The 

 diiference in the habits of the two forms is attributed to the snyness, 

 wariness, and wildness which are the natural outcome of experience 

 which accompanies maturity, (h) To have any standing, a subspecies 

 must be shown to have a distinct breeding range, which they assert has 

 not been established in the case of the Red-leg. The vague generalization 

 that it is a more northern breeder does not constitute a delimitation of a 

 clearly defined breeding range. 



Dr. Miles D. Pirnie made an exhaustive study of this species, and 

 was the first to describe the two annual plumages, and to point out the 

 differences between the male and the female plumages. He was unable 

 to find any evidence of two different races in the Black Duck, and con- 

 cluded that the subspecific characteristics which other authorities had 

 used were due to sex, age, and moult. The earlier migrants, usually re- 

 garded as the Common Black Duck, were, he found, birds in immature 

 plumage or adults still in their postnuptial moult; many of these latter, 

 having completed the moult would, a few weeks later, show the charac- 

 teristics of the Red-legged Black Duck. He found also that there was a 

 great deal of variation between birds of equal age, and even between 

 birds of the same brood. 



Florida Duck 



Anas fulvigula fulvigula 

 (a-nas, ful-vig-u-la) 



Colour Plate No. 8. Downy Young No. 33. 



SCIENTIFIC NAME 



Anas, Latin, meaning a duck; fulvigula, from Latin fulvus, meaning tawny, 

 reddish, and gula, meaning throat. 



COLLOQUIAL NAMES 



Probably the same as for Mottled Duck. 



DESCRIPTION 



ADULTS, BOTH SEXES. WINTER PLUMAGE: Practically identical with Black 

 Duck, though somewhat smaller and differing as stated below. Feathers of sides 

 of chest of male show central U-shaped buffy marking; similar feathers on female 

 show centra] buffy streak. 



ECLIPSE AND AUTUMN PLUMAGES: Same as those of Black Duck. 

 JUVENILE. Similar to Mottled Duck. 



