16 



seen eggs laid upon a mere handful of sheep's wool, but instances are on 

 record where sticks have been piled up to the height of 10 or 12 feet 

 in order to provide a foundation for the nest (See Yarrell, II, p. 308). 



The lining consists chiefly of wool; but other materials are also used 

 at times, such as dead leaves, straw, paper, shavings, rags, dung, fur, feathers 

 and cow-hair. Sometimes a little clay is also found. 



Nests built in the open vary in type. Some which I examined in 

 Shropshire in 1901 were very bulky structures, built in spruce firs. The 

 older nests were placed on the foundation of a previous year's nest and 

 were not domed, but had a high circular wall of sticks built up round 

 them a foot or more high. Other nests have been described (North Staff. 

 Field Club Report, 1901) as 27 in. deep and 24 in. in diameter, domed 

 with twigs (not thorns), with only one entrance. Newly built nests are 

 much shallower and more flimsy in construction than those which have 

 been used for two or three years. 

 Eggs. The usual clutch is 4 to 6 in number, but in some districts 7 eggs 



are not uncommon, and in dry seasons 3 are said to constitute a full clutch. 

 They differ from those of the genus Corvus in their very pale greenish 

 blue ground colour and more sparse markings. Some eggs are so finely 

 freckled that they might almost pass for those of Nucifraga, while others 

 are very boldly blotched with dark olive brown with underlying patches 

 of ash-grey. In a few cases they have been found almost without markings. 

 The eggs of this species (and also of C. frugilegus) are sometimes found 

 smeared with clay, possibly intentionally, and occasionally the eggs are 

 covered up with the nest lining. 

 Breeding I^ England the eggs are laid from about April 20 to May 5, but 



Season, from April 25 to May 1 is the best time, and when the first laying is 

 taken a second is deposited ten days later. In Ireland the latter half of April 

 is the usual time (Ussher). Rey gives April 16 — 29 as the usual date for 

 the Halle a Saale district, and curiously enough in south Spain the laying 

 season is if anything rather later, full clutches being found about April 26. 

 Measure- British eggs appear to be slightly larger than continental. 50 Con- 



sents, tinental eggs average 33.7 x 25.2 mm. (Rey), 50 British eggs, 35.47 X 25.32 

 mm. Mean average (100 eggs) 34.58 X 25.27 mm.. Max. 40.6 X 25.5 and 

 33 X 29.7 mm., Min. 30 X 22.3 mm. An abnormally long egg measures 

 45.7 X 21 mm. (Carlisle, R. H. Read). Average weight (50 eggs), 763 mg. 

 (Rey). 4 full eggs average 12.26 g. (Foster). 



Geographical Races, 

 a. Swedish Jackdaw, Coloeiis monediila moiiedula (L.). 



Local Names: Norway: Kaje, Kaa, Bavrikate. Sweden: Kdja, Kyrk- 

 Mja, Allika, Tornkraka, Svartfagel. 



