442 THE DIVERS 



is of the slightest possible nature, and consists of a few bents or rushes, and perhaps 

 a few heather twigs round the eggs, or in some cases little except the down-trodden 

 grass, yet as a rule the nests are decidedly more substantial than those of the black- 

 throated-diver. (PI. LXXVII.) The eggs are normally 2, though sometimes 1 only, 

 and are smaller than those of the other species, ranging from deep umber or 

 chocolate-brown to olivaceous, spotted sparingly as a rule with black. (PI. W.) 

 Average size of 101 eggs, 2*89 x 1'82 in. [73'5 x 46 '4 mm.]. Incubation is performed 

 by both parents in turn (Hantzsch), and the male has been shot from the eggs 

 (Ibis, 1900, p. 492). Faber estimates the period at 24 to 28 days. It is a later 

 breeder than the blackthroated-diver, and in Scotland eggs may be obtained from 

 about the middle of May onward, and second or third layings through June and 

 even in July. In Sweden the eggs are rarely found before mid-June, sometimes 

 not till July. In Iceland the first eggs are laid early in June. Only one brood 

 is reared in the season. [F. c. K. J.] 



5. Food. Mainly but not entirely a fish eater. During the winter months 

 it has been recorded as feeding on herrings : Thompson says that six, from four 

 to six inches long, were taken from one bird, and Aplin states that sixteen were 

 found hi another. Blake Knox includes in its dietary flat fish (especially flounders), 

 herrings, and coal-fish (pollack), but regards herring as the staple food. T. E. 

 Gunn records four dace, three perch, two gudgeon, and two white worms, 8J inches 

 long, in an adult female. Another contained three small flounders. Bolam thinks 

 flounders are the staple food, but has also found many sand-eels (Ammodytes tobianus), 

 some very small; also a shore-crab. Molluscs and crustaceans are also eaten, 

 according to Saunders ; E. T. Booth specifies shrimps, and Newton mentions Apos. 

 The young are fed, according to E. Selous, chiefly on sand-eels, by both parents. 

 [F. c. K. J.] 



The following species is described in the supplementary chapter on "Rare 

 Birds" : 



Whitebilled-Diver, Odvia addmsii (Gray) [Colymbus addmsi, Gray]. 



[F. c. R. J.] 



