120 Mr. G. M. Mathews on the [Ibis, 



predominates, as in the edging of the back-feathers, the 

 rump, and the upper surface of the tail ; the other in which 

 the upper surface is greyer, that being the colour of the 

 rump and the edging of the back-feathers, which, however, in 

 quite old specimens is replaced by scarlet tips, while then 

 the upper surface of the tail becomes blue. This is the 

 sole south-western species. A north-eastern and a north- 

 western species, adscitus (fig. 4) and venustus (fig. 8), agree 

 in showing pale yellow backs with the cheeks parti-coloured, 

 but otherwise are remarkably different in that one tends to 

 albinism and the other to melanism, using these words in a 

 specific sense. The all)inistic adscitus has the head and 

 back pale yellow, in the former place tending to white and 

 extending on to the throat. The yellow of the back only 

 refers, of course, to the broad edges, the bases being as 

 usual black ; the rump is of a diflFerent colour, varying 

 from grey to blue, while the underparts are bluish, differing 

 in localities from greyish to greenish blue. This species is 

 of remarkable coloration, but is as peculiar for its instability, 

 almost every mature specimen showing variation in extent 

 and depth of the yellow coloration. It appears, however, 

 to have passed the green stage in the immature, young birds 

 showing a similar but duller coloration to the mature, with 

 the head, however, speckled with blackish tips. 



The north-western species, P. venustus, has the head black, 

 the back black with yellow edges, the rump and under surface 

 yellow, the feathers tipped with black, while the bases are 

 black. The cheeks are parti-coloured blue and white, and 

 the tail is blue. This species, again, has passed the green 

 immature stage, as the young are quite like the adults. 



The last species, P. eximius (fig. 5), has perhaps the most 

 beautiful coloration of the series, and the specific name 

 seems well chosen. The head and breast are bright scarlet, 

 the lower breast golden -yellow, the abdomen green, and the 

 under tail-coverts scarlet ; the cheeks white ; the black 

 back scalloped with golden - green, the rump yellowish 

 green, and the two middle tail-feathers green, the rest dull 

 blue. The species occurs in the east from New South 

 "^'^ales to Tasmania. 



