PRELIMINARY CLASSIFIED NOTES 415 



the work of building, and the male will bring additional matter after incubation 

 has begun. The eggs vary as a rule from 4 to 6 in number, exceptionally 7, and are 

 the smallest of the European grebes' eggs. Though bluish white when quite fresh, 

 they become rapidly stained, and may be found bright red where there is much 

 ferrous oxide in suspension in the water, or deep red-brown in peat-bogs. (PL W.) 

 Average size of 72 eggs, 1/48 x 1*02 in. [37'8 x 26'1 mm.]. Both sexes share in 

 incubation, and the period is estimated at 18 to 20 days (Oswin Lee), 20 to 21 days 

 (Naumann). Apparently incubation begins with the first egg, or else the heat of 

 the nest causes the eggs to develop, for the young are not hatched simultaneously. 

 Eggs have occasionally been found in March, but the more usual time is April, 

 and as eggs have been met with from May to September, it is almost certain that 

 more than one brood is reared during the season. Probably normally the first 

 clutch is laid in April and the second in June. [F. c. E. j.] 



5. Food. Aquatic insects and their larvae, small fish, tadpoles, and water- 

 weeds. The young are fed by both parents, [w. p. p.] 



