16 THE ZOOLOGIST. 



p. 152), always in a domesticated state. These ducks sometimes 

 live to a great age. My father had one which was believed to be 

 twenty-nine years old, and I have another, in perfect male attire, 

 believed to be now ten years old : this is the same bird which a 

 decoy-drake treated as a veritable male and bullied, while his 

 own mate looked placidly on. The Tufted Duck mentioned by 

 Mr. Macpherson was twelve years old. 



In passing, it may be remarked a ready way which may be 

 adopted of acertaining the sex of Mergansers, which I have tried 

 in Leadenhall Market, is by passing the finger and thumb down 

 the neck and feeling for the enlargement of the trachea. But 

 such a test would be of no avail in the Wigeon and Tufted 

 Ducks. 



Mr. Coburn does not state that the ovary of the Merganser 

 examined by him was diseased, and in my father's specimen 

 there was no sign of disease, so probably they were both healthy 

 birds. The diseased condition of the ovary which is sometimes 

 presented in a hen Pheasant may be seen in Yarrell's illustration 

 on page 103 of vol. iii. of his ' British Birds.' Yarrell, it will be 

 remembered, was of opinion that disease always accompanied the 

 change of plumage ; but birds may recover from disease with or 

 without any resumption of the normal colour ; a hen Pheasant 

 of this description, which was caged by my father, recovered its 

 ordinary female plumage. Again, there may be a diseased condi- 

 tion of the ovaries without any indication of it by a change of 

 plumage. 



It would be interesting to know whether, after this change 

 of plumage, the Anatidce are capable of laying fertile eggs. 

 Gallinaceous birds almost always become barren, but apparently 

 some Passerine birds do not, such as Redstarts and Bed-backed 

 Shrikes, though there does not appear to be any ascertained cases 

 of their having reared young. 



There is a recorded instance, and only one, so far as I am 

 aware, of a domestic hen in cock's plumage producing young. 

 This is mentioned in * The Field' of Nov. 1st, 1884. This seems 

 to be the only incontestable instance of any female bird in male 

 plumage having young ones — or perhaps I should say recorded 

 instance of what may occasionally happen and nevertheless 

 escape notice. 



I have seen certainly four, if not five, female Redstarts 



