£n8 Mattingley, Thermometer-Bird or Mallee-Foivl. [isf"oct 



against the windy weather that blows from those quarters. As 

 the outer covering of the mounds in Mallee country is composed 

 chiefly of sand, this breakwind prevents the undue displacement 

 of the superimposed material. The choosing of a site where the 

 rays of the sun can fall upon the mound and warm it, as well as 

 the selection of a place where the mound is protected by a 

 breakwind, together with the circular style of architecture of the 

 mound, which renders it less liable to damage by wind, empha- 

 sizes the truly marvellous knowledge of the laws of physics 

 possessed by the Mallee-Hens. Although the mounds are con- 

 structed as a rule in these sites in the Mallee, yet I have 

 examined a mound which had been built in the centre of a patch 

 of scrub, the stems of which stuck up through the mound in all 

 directions, whilst the leaves of the Mallee scrub overhead 

 shielded the mound to a certain extent from the sun's rays. 

 Within the egg-chamber of this mound, however, there was a 

 greater supply of decomposing vegetable matter, to create 

 greater heat. Mr. Charles M'Lennan, better known as " Mallee- 

 Bird," who has had over 20 years' experience of the ways of the 

 Lipoa, and who has greatly assisted me in my investigations of 

 the life-history of these birds, informs me that he has found the 

 Lowans utilizing the heaps of sand thrown out of a rabbit 

 warren for building their mound, which they had erected in the 

 centre of the burrows, thereby saving a large amount of toil, 

 which represented a fortnight's work for the birds. In other 

 districts, outside the Mallee area, which the Lipoa frequents, and 

 which is closed with scrub, the birds choose sites in accordance 

 with the above conditions as far as possible. Many mounds are 

 found in the troughs between the sand-dunes in the Mallee or in 

 depressions in these arid places, yet there are many exceptions 

 to this rule, The theory that the mounds are placed in these 

 depressions so as to get a greater supply of moisture to aid in 

 the fermentative action does not apparently hold good. The 

 mounds are placed in these sites for protection from the wind, 

 as well as to obtain the advantage of the higher and more even 

 temperature prevailing in these miniature valleys. 



Structure and Material of Mound. — The foundation 

 of the mound of the Lipoa, which is the smallest structure of all 

 the Australian mould-builders, is formed by first scratching out 

 a circular depression in the ground about 2 feet wide and i foot 

 deep. The sand or gravel is next scraped up and placed around 

 this circular hollow, and so the outside wall of the nesting mound 

 is formed. When completed the height of the mound ranges 

 from 2 ft. 6 in. to 3 ft. 6 in., with a diameter at the base of 

 between 12 feet and 18 feet. The size of the mounds varies from 

 1 10 cubic feet of material to 200 cubic feet. Only a pair of 

 birds works at the same mound, and into the concavity, which 

 now has the appearance of the crater of a miniature volcano, 



