DR. THEODOR NEUMANN. 153 



its bead and, after surveying the intruder for a moment, 

 retires into the seclusion of its domicile. It will repeat 

 this process several times, but at last loses patience at 

 the frequent interruptions of its quiet, and takes to 

 flight. 



One step farther vv^ill bring us to those birds which 

 make a real attempt at nest-building, with results, how- 

 ever, which do not deserve that name at all, as they are 

 merely heaps of leaves and grasses collected together on 

 the ground, or in a small hollow in the ground, and with 

 a very slight depression, caused apparently quite as 

 much by the weight of the eggs as by the art; of the bird. 

 Such artless nests are built by the nightingale (Luscinia 

 lusciola), the lark (Alauda campestnis), the snipe (Scolo- 

 pax gallinago), the sparrow (Passer domesticus), the 

 swan (Cygnus olor), etc. 



Others, especially Australian birds, for instance the 

 mound-bird or jungle-fowl (Megapodius tumulus), deposit 

 their eggs in a heap of sand, or an accumulation of dead 

 leaves, and trust to the heat of the sun, assisted in the 

 latter case by the warmth produced by the decay of the 

 vegetable matter, to maintain the temperature necessary 

 for the evolution of the young. The brush turkey 

 (Tallegalla Lathami) for instance collects an immense 

 heap of decaying vegetable matter as a bed for the eggs, 

 and the parents work on this structure not only for days, 

 but weeks and months, nay, they add to it year after 

 year, so that travellers have found cones of fifteen feet 

 height and sixty feet in circumference. Of course this 

 can not be the work of one single pair, but is the result 

 of the united efforts of many. The way of carrying the 

 materials is also rather peculiar, as the birds do not use 

 their bills, but grasp a quantity of leaves, or whatever 

 they want to use, with their powerful feet and throw it 

 backward toward one point, so that the ground around is 

 cleared for considerable distances, and no grass or leaf 



91 



