.AN* ^ ^ 





NOVITATES ZOOLOGICAE. 



Vol. XXV. MAY 1918, No. I. 



THE COLOUR CHANGES OF THE BEAK AND SHIELD 



OF THE YOUNG MOORHEN (GaUinula c. chloropus). 



By FRANCES PITT. 



(Plate II.) 



WHEN hatched the colouring of the young Moorhen is striking in the 

 extreme, its perfectly black down throwing into vivid relief the scarlet 

 of its bill and shield and the patches of blue skin on its forehead, which can be 

 plainly seen through the sparse covering of a few hair-like bits of down. On 

 close examination the " blue " proves to be really blue-grey, but by contrast 

 with the red of the shield appears an almost cobalt blue. The colouring seems 

 to be in some measure due to the dark eyeballs showing through the semi-trans- 

 parent skin, and it extends from above either eye and nearlj' meets in the middle 

 of the forehead. The head is so scantUy covered with down that not only the 

 blue areas, but the pinky-yellow skin of the skuU is also visible, and adds much 

 to the chick's weird bald-headed ai3pearance. The efl'ect is stiU further added 

 to by the white tips of the bits of down above each eye, which makes it look 

 as if it had grey eyebrows, and by the simOar white hau-s on its throat, so that 

 the young Moorhen irresistibly reminds the observer of a little bald-headed old 

 man with a straggling grey beard. 



When the chick is excited, for instance when it is appealmg with quivering 

 wings and anxious " cheeps " to its parents for food, the hairs of its head lie 

 flat to the skin, but when fed, contented, and happy, the hairs are elevated, and 

 stand on end so that the remarkable tints of the sldn beneath are even more 

 noticeable than before. 



The bill is, of com'se, the most brilliant item in the young Moorhen's colour 

 scheme, the shield, extending up the forehead, being of a particularly beautiful 

 and vividly transparent red, which half way down the biU gives way to a greenish 

 tint that at the tip merges into yellow. This colourmg persists while the chicks 

 are dependent on their parents, and Mr. J. R. B. ilasefield has suggested to 

 me that this points to it servmg as a recognition mark and enables the parents 

 to find the young quickly when they are hidden among rushes and other water- 

 side vegetation. The theory is a most tempting one, ofiering as it does an 

 explanation of the remarkable and conspicuous appearance of the chicks, but 

 when watching Moorhens and their young I have not seen anything to confirm 

 it. On the contrary, when the young ones do leave the nest — which, provided 



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