PRELIMINARY CLASSIFIED NOTES 243 



chiefly composed of dead leaves of flag or reed, though occasionally other materials 

 may be used, such as coarse grasses, etc. (PI. Lxvni.) It bears a curious likeness 

 to that of the coot, and is apparently built by the duck. Some nests have little or 

 no down even when the eggs are much incubated, but generally there is a fair 

 supply when the duck has been sitting some time. Mr. H. Noble describes the 

 down as large and exceedingly soft to the touch : it is rather dark brownish grey, 

 and has the usual light centres but no light tips, and is not by itself sufficient for 

 identification without the nest feathers, which are figured and described by Mr. 

 H. Noble in British Birds, ii. p. 23, pi. i. They are ' large and brownish in colour, 

 slightly streaked from the centre upwards, and often tipped for a quarter of an 

 inch with grey' (Noble.) (See also PI. U.) The eggs, however, are characteristic, 

 being large and very broad in shape. The shell is smooth and waxy, and the 

 colour varies from greenish grey to greenish drab, occasionally almost a dull 

 leaden colour, but the greenish tinge, though somewhat fugitive, is rarely 

 wanting. The clutch usually ranges from 6 or 7 to 11 in number, and 13 and 

 14 have been found in one nest. Not infrequently one or more eggs may 

 be found hi the water close to the nest, presumably knocked out by the 

 duck accidentally. Average size of 100 eggs, 2-42x1-72 in. [61-4x43-7 mm.]. 

 (PI. S.) Incubation is performed by the female alone, and the period is given by 

 Naumann as 23 days, and 24 by the Hon. G. Legge. If correct, this is rather 

 shorter than what might be expected. The average date for full clutches in 

 England is given by most writers as about the second week of May or the middle 

 of that month. In some cases the eggs must be laid nearly a month earlier, for 

 I have seen eggs which could not have been laid later than mid- April, and know of 

 numerous cases in which full clutches have been found from 21st April to 2nd May. 

 In Scotland fresh eggs may be found till well into June. Only a single brood is 

 reared in the season. [F. c. B. j.] 



5. Food. Except during the winter months the bulk of the food of this 

 species consists of vegetable matter, chiefly the young shoots, buds, leaves, and 

 seeds of the aquatic plants which it obtains by diving. Among these may be 

 mentioned Polygonum amphibium, which Naumann found in great plenty, and in 

 autumn Potamogeton marinus and P. pectinatus. Other plants recorded are 

 Myriophyllum, Ceratophyllum, and seeds of reed, rushes, and grasses. Jackel records 

 also Panicum crus-galli, Olyceria fluitans, Polygonum persicaria, P. hydropiper, and 

 P. lapathifolium, as well as Bidens tripartite,. Aquatic insects are also eaten occa- 

 sionally, and no doubt also small frogs. During the winter small fish are taken as 



