Some Bird Architects. 



uncommon occurrence in sheltered shrubberies to find 

 both nest and eggs by the end of February. Although 

 the bird will build its nest almost anywhere in bushes, 

 trees, and hedgerows, it nevertheless devotes some time 

 to the selection of the site, and I have seen on occasion 

 bitter fights take place between rivals for a coveted 

 spot. Once the position has been settled the build- 

 ing is commenced, and is carried forward with won- 

 derful precision, skill, and rapidity. All day long the 

 work goes on, the patient little architect bringing moss 

 and slender twigs, dry grasses, and similar material, 

 which is skilfully woven into the familiar ample cup- 

 shaped nest, and reinforced with an ample supply of 

 mud well worked into the foundations. Then comes 

 the lining of the nest, which shows the Thrush not 

 only as a skilful weaver, but as an expert plasterer and 

 mason ; for the bird now makes a cement composed of 

 an admixture of mud, rotten wood, and cow dung in 

 varying proportions, and with this coats the whole of 

 the interior of the nest, the walls of which become 

 converted into a perfectly smooth, damp-proof, cup- 

 shaped receptacle for the safe housing of the precious 

 eggs. Sad to say, this expert masonry on the part of 

 the parent Thrush sometimes leads to disaster, an un- 

 usually prolonged downpour of heavy rain filling the 

 nest and drowning the nestlings. 



The art of nest-building is an acquired habit, and 

 the evolution from the simplest form to the most com- 

 plex type of construction can be traced step by step 

 in the selection of site, materials, and shape of the 

 completed nest. " That the earliest birds were arboreal 

 in their habits there can be little room for doubt, and 



