Family CAPRIMULGIDAE. 



Caprimulgus europaeus L. — Nightjar. 



(Plate 92, fig. a-c). 

 (Snouckaert: Avifauna Neerlandica, page 54, No. 130). 



Colour of surface of shell: 

 Colour of spots: 



Average dimensions: 

 Average weight of shell 

 Texture of shell: 

 Shape : 



Breeding-site : 



Number of eggs: 

 Breeding season: 

 Duration of incubation: 

 * Remarks : 



milk white or faintly dirty white. (See the 

 subjoined remarks). *) 



brown, in various tints; underlying spots and 

 streaks are of a bluish-grey colour, and give 

 a marbled appearance to the eggs; some- 

 times but little is to be seen of these under- 

 lying spots, the markings then consisting 

 chiefly of sharply outlined spots deposited 

 on the surface and which leave a large 

 part of clear underground visible. The 

 difference between the markings of the 

 two eggs of one set is frequently very 

 considerable. 



31 X 21.9 millimetres. 



0.54 gram. 



fine-grained. 



oval; in by far the most eggs, the big end 

 cannot be distinguished from the pointed end. 



on the bare sand or on moss, in open spots 

 covered with heather and shrubs, in a 

 shady spot, mostly quite near a shrub, 

 and by preference in a spot where there 

 is some gravel; also sometimes on mossy 

 tree stumps. 



two. 



June (sometimes late in May) — July. 



about 17 days. 



In the Catalogue of the Collection of Birds' eggs in the 

 British Museum (Vol. Ill, page 71) those eggs are 

 described as a separate type which although having 

 normal markings, have a cream-or pa\e salmon-colou- 

 red underground The cream-coloured eggs should, in 

 my opinion, be regarded as transitions towards-and 

 the salmon-coloured eggs (of which the markings 

 will no doubt be a darker shade of the same colour) 

 as belonging to the real erythristic variations of 

 the ordinary type. 



In this connection it may be stated here that accor- 

 ding to certain descriptions '), in the case of several 

 exotic Caprimulgus-species the erythristic colouring 

 seems to be the normal one or at any rate fre- 

 quently occurs. 



') See the above mentioned Catalogue, Vol. Ill (London 1903) pages 67—74, and NEHRKORN, 

 Katalog der Eiersammlung (II. Aufl., Berlin, 1910), pages 130—132. 



