GENERAL AND INTRODUCTORY. 33 



commence from the outside area of a very considerable space, and gradually work 

 in towards the centre. Examples of this species, were some years since successfully 

 kept at the London Zoological Gardens, and exhibited there their characteristic nest- 

 building habits, and deposited eggs, which were duly hatched. It was observed, under 

 these artificial conditions, that the male bird paid considerable attention to the eggs 

 when deposited, always maintaining a perpendicular, cylindrical opening in the centre 

 of the nest-heap for the purposes of ventilation. The young birds, as soon as hatched, 

 were for the first twelve hours kept covered up in the material of the inound, but 

 on the following day emerged with their wing-feathers well developed, but encased in 

 membranous sheaths, which soon burst, leaving the limb completely free. .On the 

 third day the young birds were capable of strong flight. The relatively large size of 

 the eggs, and the egress of the birds from them in a more highly advanced state of 

 development than obtains with any other known species, is common to all of the 

 members of this remarkable family, and is held to be a fact indicative of their 

 remote ancestry. In the case of Megapodium, it has been observed that the mound- 

 constructing instinct is so strongly ingrained by heredity, that young birds taken 

 fresh from the nest, and confined under favourable conditions, have at once commenced 

 to construct mounds after the characteristic manner of their tribe. 



The third member of the Megapodidte or Mound-builders is the handsome bird 

 Leipoa ocellata, known in South Australia as the Leipoa or Native Pheasant, and in 

 Western Australia as the Gnow. This species has much the form of a pheasant, but 

 in its shorter tail and ocellated markings more nearly resembles the Indian Tragopan, 

 Ceriornis Lathami. The mound constructed by the Leipoa is relatively small, compared 

 with that of the Talegalla and Megapodium, rarely exceeding eight or nine feet in 

 diameter, and two or three feet in height. A larger quantity of sand and soil 

 being, moreover, mixed with the vegetable substances, it acquires so much more solid 

 a consistence that it may be readily mistaken for an ant-heap. For the table this 

 species is esteemed more highly than the two preceding forms, the eggs also, of which 

 about a dozen are deposited in a single nest, being greatly prized. 



One of the most essentially Australian bird groups is that of the Bower Birds, 

 usually relegated by ornithologists to a position near the Starlings, and remarkable, as 

 in the case of the Megapodidte, for their architectural propensities. In this instance, 

 however, the edifice raised is a supplementary structure in no way associated with the 

 nidamental functions that characterise the mound of the Megapodidre, for which 



purpose an ordinary nest is constructed. The Bower Birds, in point- of fact, possess 

 E 



