190 BIRDS OF AUSTRALIA. 



together for want of the adhesive quality of the clay, mixes 

 with it a great quantity of dried grass, stalks, &c., and thus 

 forms a firm and hard exterior, the inside of which is slightly 

 lined with dried grasses and a few feathers. The eggs differ 

 considerably in colour and in shape, some being extremely 

 lengthened, while others bear a relative proportion ; the 

 ground-colour of some is a beautiful pearl white, of others a 

 very pale buff; their markings also differ considerably in form 

 and disposition, being in some instances wholly confined to 

 the larger end, in others distributed over the whole of the 

 surface, but always inclined to form a zone at the larger end ; 

 in some these markings are of a deep chestnut-red, in others 

 light red, intermingled with large clouded spots of grey ap- 

 pearing as if beneath the surface of the shell. The eggs are 

 generally four, but sometimes only two in number; their 

 average length is one inch and three lines, and their breadth 

 nine lines. 



The sexes are very similar in size, but the female may 

 at all' times be distinguished from the male by her white 

 forehead and throat, a fact I determined many times by actual 

 dissection, thus showing the fallacy of the opinion enter- 

 tained by some naturalists of there being two distinct species. 



The male has a line over the eye, a patch on each side of 

 the neck, a longitudinal stripe on the wing, tips of the 

 secondaries, rump, upper tail- coverts, the basal two-thirds 

 and the tips of the tail, under surface of the shoulder, breast, 

 flanks, abdomen, and under tail-coverts white ; the remainder 

 of the plumage black, with a deep bluish tinge on the head, 

 throat, chest, and back, and a green tinge on the primaries 

 and tail ; bill yellowish white ; irides straw-yellow ; feet 

 black. 



The female differs in having the forehead, lores, and chin 

 white. The young on leaving the nest have the irides black ; 

 in other respects they resemble their parents, but are of 

 course far less brilliant in colour. 



