RESULTS OF CASTRATION IN DUCKS. 4I 



uniform slate and gray vermiculated types. There is also a 

 peculiar tuft of small feathers just anterior to the junction of 

 the wing and body. Each feather (Fig. 8, A) has a narrow band 

 of slate and light gray vermiculations across the tip, then a 

 curved band of light claret, the remainder being a mixture of 

 slate and gray. 



Male in Summer Plumage. — Top of head: almost identical 

 with normal type, but much less brilliant. Light line above eye: 

 distal half mostly buff with small irregular blotches of black; 

 base, dull black; sometimes the entire feather is nearly black. 

 Beneath the eye: dull black; distal half with buff edges. Throat: 

 reddish buff with irregular dull black marks; basal half slate. 

 Upper breast: (Fig. 4, C) bands of reddish buff or claret and dull 

 black; though irregular they are more or less transverse; basal 

 half: slate. Regular patterns may occur (Fig. 4, D). Lower 

 breast: buff in place of reddish buff; otherwise as preceding; 

 sometimes feathers like those of one of the female types are 

 found (Fig. 5, D). Anterior keel: (Fig. 5, C) mostly slate; mar- 

 gin of varying width vermiculated with gray; tip usually of rufus 

 shade. Posterior keel : dull slate, vermiculated margins reduced 

 or absent. Posterior to vent: dull black with vermiculated mar- 

 gins. Under tail coverts: dull black with narrow buff margin on 

 exposed part, sometimes vermiculated. Sides of body posterior 

 to wing: (Fig. 8, H) slate with narrow gray vermiculations. 

 Dorsal surface of body: modifications often slight throughout; 

 the feathers at union of neck with body (Fig. 6, C) lose most of 

 their vermiculations and may have buff edges. Scapulars: dull 

 slate. Laterals somewhat modified, often with a distinct tend- 

 ency for the formation of transverse reddish buff and black 

 bands across the tip, similar to those of the breast; vermicu- 

 lations reduced or absent. 



Female. — Top of head: distal half, dull greenish black with 

 buff margins; basal half slate. Line above eye: reddish buff 

 with median dark stripe; basal half slate. Throat: reddish buff 

 with gray base. Upper neck at junction with next section: buff 

 with irregular longitudinal dark stripes; base slate. Breast: 

 buff, sometimes reddish, with dark patches, arranged in numerous 

 patterns (Fig. 4, E-H). Keel: (Fig. 5, £, F) similar to preceding 



